Index: src/com/iver/cit/gvsig/fmap/rendering/FInterval.java
===================================================================
--- src/com/iver/cit/gvsig/fmap/rendering/FInterval.java	(revision 32356)
+++ src/com/iver/cit/gvsig/fmap/rendering/FInterval.java	(working copy)
@@ -40,6 +40,9 @@
  */
 package com.iver.cit.gvsig.fmap.rendering;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import com.hardcode.gdbms.engine.values.DateValue;
 import com.hardcode.gdbms.engine.values.DoubleValue;
 import com.hardcode.gdbms.engine.values.FloatValue;
@@ -124,23 +127,17 @@
 	 * @return FInterval nuevo.
 	 */
 	public static IInterval create(String s) {
-		String[] str = s.split("-");
-		if (s.startsWith("-")) {
-			str[0]="-"+str[1];
-			s.replaceFirst("-","");
-			str[1]=str[2];
-		}
-		if (s.contentEquals(new StringBuffer("--"))) {
-			str[1]=s.substring(s.indexOf('-')+1,s.length()-1);
+		Pattern pattern = Pattern.compile("(-?[^-]*)-(-?.*)");
+		Matcher matcher = pattern.matcher(s);
+		IInterval inter=new NullIntervalValue(); // temporal pessimism
+		if (matcher.find()) {
+			try{
+				inter = new FInterval(Double.parseDouble(matcher.group(1)),
+						Double.parseDouble(matcher.group(2)));
+			}catch (NumberFormatException e) {
+			}
 		}
 
-		IInterval inter=null;
-		try{
-		inter = new FInterval(Double.parseDouble(str[0]),
-				Double.parseDouble(str[1]));
-		}catch (NumberFormatException e) {
-			return new NullIntervalValue();
-		}
 		return inter;
 	}
 }
Index: src-test/com/iver/cit/gvsig/fmap/AllTests.java
===================================================================
--- src-test/com/iver/cit/gvsig/fmap/AllTests.java	(revision 32356)
+++ src-test/com/iver/cit/gvsig/fmap/AllTests.java	(working copy)
@@ -25,6 +25,7 @@
 import com.iver.cit.gvsig.fmap.layers.FLayer;
 import com.iver.cit.gvsig.fmap.layers.LayerFactory;
 import com.iver.cit.gvsig.fmap.layers.LayersIteratorTest;
+import com.iver.cit.gvsig.fmap.rendering.FIntervalTest;
 import com.iver.cit.gvsig.fmap.spatialindex.SpatialIndexTest;
 import com.iver.cit.gvsig.fmap.tools.AreaListenerTest;
 import com.vividsolutions.jts.operation.overlay.SnappingOverlayOperationTest;
@@ -95,6 +96,8 @@
 		suite.addTestSuite(SpatialIndexTest.class);
 		suite.addTestSuite(TestDbf.class);
 		suite.addTestSuite(TestDgn.class);
+		
+		suite.addTestSuite(FIntervalTest.class);
 
 		//$JUnit-END$
 		return suite;
Index: src-test/com/iver/cit/gvsig/fmap/rendering/FIntervalTest.java
===================================================================
--- src-test/com/iver/cit/gvsig/fmap/rendering/FIntervalTest.java	(revision 0)
+++ src-test/com/iver/cit/gvsig/fmap/rendering/FIntervalTest.java	(revision 0)
@@ -0,0 +1,22 @@
+package com.iver.cit.gvsig.fmap.rendering;
+
+import junit.framework.TestCase;
+
+public class FIntervalTest extends TestCase {
+
+	private static final double DELTA = 0.000001;
+
+	public void testNegativeIntervals() throws Exception {
+		testNegativeInterval("-2.1--1.1", -2, -1.1);
+		testNegativeInterval("-2.1-1.1", -2.1, 1.1);
+		testNegativeInterval("2.1--1", 2.1, -1);
+		testNegativeInterval("1.1-2", 1.1, 2);
+	}
+
+	private void testNegativeInterval(String intervalString, double min,
+			double max) {
+		FInterval interval = (FInterval) FInterval.create(intervalString);
+		assertTrue(interval.getMin() - min < DELTA);
+		assertTrue(interval.getMax() - max < DELTA);
+	}
+}