Index: src/uk/me/parabola/mkgmap/reader/osm/MultiPolygonToLineRelation.java
===================================================================
--- src/uk/me/parabola/mkgmap/reader/osm/MultiPolygonToLineRelation.java	(revision 0)
+++ src/uk/me/parabola/mkgmap/reader/osm/MultiPolygonToLineRelation.java	(revision 0)
@@ -0,0 +1,193 @@
+package uk.me.parabola.mkgmap.reader.osm;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import uk.me.parabola.log.Logger;
+
+public class MultiPolygonToLineRelation extends Relation {
+	private static final Logger log = Logger
+			.getLogger(MultiPolygonToLineRelation.class);
+
+	private final Map<Long, Way> tileWayMap;
+	private final Map<Long, String> roleMap = new HashMap<Long, String>();
+
+	public MultiPolygonToLineRelation(Relation other, Map<Long, Way> wayMap) {
+		this.tileWayMap = wayMap;
+
+		setId(other.getId());
+
+		if (log.isDebugEnabled()) {
+			log.debug("Construct multipolygon (lines) ", toBrowseURL());
+			log.debug("Multipolygon tags:",toTagString());
+		}
+
+		for (Map.Entry<String, Element> pair : other.getElements()) {
+			String role = pair.getKey();
+			Element el = pair.getValue();
+			if (log.isDebugEnabled()) {
+				log.debug(" ", role, el.toBrowseURL(), el.toTagString());
+			}
+			addElement(role, el);
+			roleMap.put(el.getId(), role);
+		}
+
+		setName(other.getName());
+		copyTags(other);
+	}
+
+	@Override
+	public void processElements() {
+		log.info("Processing multipolygon (lines)", toBrowseURL());
+
+		// don't care about outer and inner declaration
+		ArrayList<Way> orgWays = new ArrayList<Way>();
+
+		for (Map.Entry<String, Element> r_e : getElements()) {
+			if (r_e.getValue() instanceof Way) {
+				orgWays.add((Way) r_e.getValue());
+			} else {
+				log.warn("Non way element", r_e.getValue().getId(),
+					"in multipolygon", getId());
+			}
+		}
+
+		Way copyTagWay = new Way(FakeIdGenerator.makeFakeId());
+		if (useRelationTags()) {
+			log.debug("Use relation tags");
+			copyTagWay.copyTags(this);
+			// not interested in type=multipolygon
+			copyTagWay.deleteTag("type");
+		} else {
+			log.debug("Use tags from outer ways");
+			copyTagsFromOuterWays(orgWays, copyTagWay);
+		}
+		if (log.isDebugEnabled()) {
+			for (Entry<String, String> tag : copyTagWay.getEntryIteratable()) {
+				log.debug("-", tag.getKey(), tag.getValue());
+			}
+		}
+
+		Iterable<Entry<String, String>> tags = copyTagWay.getEntryIteratable();
+		if (tags.iterator().hasNext() == false) {
+			// no tag left
+			log.warn("Cannot process multipolygon", toBrowseURL(),
+				". The mp does not contain unambiguous tags.");
+			cleanup();
+			return;
+		}
+
+		// duplicate all ways
+		List<Way> mpResult = new ArrayList<Way>();
+		for (Way way : orgWays) {
+			if (way.isClosed() && way.getPoints().size() > 2) {
+				Way clonedWay1 = new Way(FakeIdGenerator.makeFakeId());
+				Way clonedWay2 = new Way(FakeIdGenerator.makeFakeId());
+
+				// is that necessary?
+				clonedWay1.setName(way.getName());
+				clonedWay2.setName(way.getName());
+
+				int midPoint = way.getPoints().size() / 2;
+				clonedWay1.getPoints().addAll(
+					way.getPoints().subList(0, midPoint + 1));
+				clonedWay1.getPoints().addAll(
+					way.getPoints().subList(midPoint, way.getPoints().size()));
+
+				mpResult.add(clonedWay1);
+				mpResult.add(clonedWay2);
+			} else {
+				Way clonedWay = way.copy();
+				clonedWay.setId(FakeIdGenerator.makeFakeId());
+				mpResult.add(clonedWay);
+			}
+
+			// remove all tags that are used by the polygon
+			for (Entry<String, String> wayTag : way.getEntryIteratable()) {
+				String mpTagValue = copyTagWay.getTag(wayTag.getKey());
+				if (wayTag.getValue().equals(mpTagValue)) {
+					if (log.isDebugEnabled()) {
+						log.debug("Remove tag", wayTag.getKey(), way
+								.getTag(wayTag.getKey()), "from way", way
+								.getId());
+					}
+					way.deleteTag(wayTag.getKey());
+				}
+			}
+		}
+
+		// copy the tags to the duplicated ways
+		// and put them to the way list
+		for (Way way : mpResult) {
+			way.copyTags(copyTagWay);
+			tileWayMap.put(way.getId(), way);
+		}
+		
+		// log the resulting ways
+		if (log.isDebugEnabled()) {
+			log.info("Results:");
+			for (Way way : mpResult) {
+				log.debug("-", way.getId(), way.toTagString());
+			}
+		}
+
+	}
+
+	private void cleanup() {
+		roleMap.clear();
+	}
+
+	/**
+	 * Checks if this multipolygon contains reasonable tags or if the tags must
+	 * be collected from the ways.
+	 * 
+	 * @return <code>true</code> use the tags from the relation;
+	 *         <code>false</code> use the tags from the ways
+	 */
+	private boolean useRelationTags() {
+		for (Entry<String, String> tag : this.getEntryIteratable()) {
+			// check if there is at least one tag
+			// not equal to type=multipolygon and boundary=...
+			if ("type".equals(tag.getKey()) == false
+					&& "boundary".equals(tag.getKey()) == false) {
+				return true;
+			}
+		}
+		return false;
+	}
+
+	private boolean isOuterWay(Way way) {
+		String role = roleMap.get(way.getId());
+		return (role == null || "outer".equals(role) || "exclave".equals(role));
+
+	}
+
+	private void copyTagsFromOuterWays(List<Way> allWays, Way resultWay) {
+		boolean firstWay = true;
+		for (Way mpWay : allWays) {
+			if (isOuterWay(mpWay) == false) {
+				// ignore all inner ways
+				continue;
+			}
+
+			if (firstWay) {
+				resultWay.copyTags(mpWay);
+				firstWay = false;
+			} else {
+				for (Entry<String, String> resultTag : resultWay
+						.getEntryIteratable()) {
+					// check if the tags are identical
+					if (resultTag.getValue().equals(
+						mpWay.getTag(resultTag.getKey())) == false) {
+						// remove the tag if they are not identical
+						resultWay.deleteTag(resultTag.getKey());
+					}
+				}
+			}
+		}
+	}
+
+}
Index: src/uk/me/parabola/mkgmap/reader/osm/xml/Osm5XmlHandler.java
===================================================================
--- src/uk/me/parabola/mkgmap/reader/osm/xml/Osm5XmlHandler.java	(revision 1634)
+++ src/uk/me/parabola/mkgmap/reader/osm/xml/Osm5XmlHandler.java	(working copy)
@@ -49,6 +49,7 @@
 import uk.me.parabola.mkgmap.reader.osm.FakeIdGenerator;
 import uk.me.parabola.mkgmap.reader.osm.GeneralRelation;
 import uk.me.parabola.mkgmap.reader.osm.MultiPolygonRelation;
+import uk.me.parabola.mkgmap.reader.osm.MultiPolygonToLineRelation;
 import uk.me.parabola.mkgmap.reader.osm.Node;
 import uk.me.parabola.mkgmap.reader.osm.OsmConverter;
 import uk.me.parabola.mkgmap.reader.osm.Relation;
@@ -602,8 +603,15 @@
 		String type = currentRelation.getTag("type");
 		if (type != null) {
 			if ("multipolygon".equals(type)) {
-				Area mpBbox = (bbox != null ? bbox : ((MapDetails) collector).getBounds());
-				currentRelation = new MultiPolygonRelation(currentRelation, wayMap, mpBbox);
+				if (currentRelation.getTag("boundary") != null) {
+					currentRelation = new MultiPolygonToLineRelation(
+							currentRelation, wayMap);
+				} else {
+					Area mpBbox = (bbox != null ? bbox
+							: ((MapDetails) collector).getBounds());
+					currentRelation = new MultiPolygonRelation(currentRelation,
+							wayMap, mpBbox);
+				}
 			} else if("restriction".equals(type)) {
 
 				if(ignoreTurnRestrictions)