=== modified file 'scour.py'
--- scour.py	2011-02-11 00:48:53 +0000
+++ scour.py	2011-02-11 16:01:08 +0000
@@ -596,8 +596,9 @@
 	"""
 	global numElemsRemoved
 	num = 0
+	
+	# Remove certain unreferenced elements outside of defs
 	removeTags = ['linearGradient', 'radialGradient', 'pattern']
-
 	identifiedElements = findElementsWithId(doc.documentElement)
 	referencedIDs = findReferencedElements(doc.documentElement)
 
@@ -609,8 +610,7 @@
 				num += 1
 				numElemsRemoved += 1
 
-	# TODO: should also go through defs and vacuum it
-	num = 0
+	# Remove most unreferenced elements inside defs
 	defs = doc.documentElement.getElementsByTagName('defs')
 	for aDef in defs:
 		elemsToRemove = removeUnusedDefs(doc, aDef)
@@ -2784,15 +2784,21 @@
 	if options.remove_metadata:
 		removeMetadataElements(doc)
 	
+	# remove unreferenced gradients/patterns outside of defs
+	# and most unreferenced elements inside of defs
+	while removeUnreferencedElements(doc) > 0:
+		pass
+
 	# remove empty defs, metadata, g
-	# NOTE: these elements will be removed even if they have (invalid) text nodes
-	elemsToRemove = []
+	# NOTE: these elements will be removed if they just have whitespace-only text nodes
 	for tag in ['defs', 'metadata', 'g'] :
 		for elem in doc.documentElement.getElementsByTagName(tag) :
 			removeElem = not elem.hasChildNodes()
 			if removeElem == False :
 				for child in elem.childNodes :
-					if child.nodeType in [1, 3, 4, 8] :
+					if child.nodeType in [1, 4, 8]:
+						break
+					elif child.nodeType == 3 and not child.nodeValue.isspace():
 						break
 				else:
 					removeElem = True
@@ -2800,10 +2806,6 @@
 				elem.parentNode.removeChild(elem)
 				numElemsRemoved += 1
 
-	# remove unreferenced gradients/patterns outside of defs
-	while removeUnreferencedElements(doc) > 0:
-		pass
-
 	if options.strip_ids:
 		bContinueLooping = True
 		while bContinueLooping:

=== modified file 'testscour.py'
--- testscour.py	2011-02-11 00:48:53 +0000
+++ testscour.py	2011-02-11 16:04:10 +0000
@@ -1205,6 +1205,12 @@
 		self.assertEquals(doc.getElementsByTagName('path')[10].getAttribute('fill-rule'), '',
 			'Default attribute not removed, although its parent used default');
 
+class RemoveDefsWithUnreferencedElements(unittest.TestCase):
+	def runTest(self):
+		doc = scour.scourXmlFile('unittests/useless-defs.svg')
+		self.assertEquals(doc.getElementsByTagName('defs').length, 0,
+			'Unremoved defs, although it contains only unreferenced elements');
+
 # TODO: write tests for --enable-viewboxing
 # TODO; write a test for embedding rasters
 # TODO: write a test for --disable-embed-rasters

=== added file 'unittests/useless-defs.svg'
--- unittests/useless-defs.svg	1970-01-01 00:00:00 +0000
+++ unittests/useless-defs.svg	2011-02-11 13:33:24 +0000
@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns="http://www.w3.org/2000/svg">
+  <defs id="defs_one">
+    <linearGradient id="testgradient">
+      <stop style="stop-color:#e4ff01" offset="0"/>
+      <stop style="stop-color:#befb00" offset=".36267"/>
+      <stop style="stop-color:#216908" offset=".78168"/>
+      <stop style="stop-color:#0a2002" offset="1"/>
+    </linearGradient>
+    <filter id="CDS" x="-0.2" y="0.2" width="1.4" height="1.4">
+      <feGaussianBlur stdDeviation="8"/>
+      <feColorMatrix values="1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0.6 0"/>
+    </filter>
+    <pattern id="testpattern">
+        <rect x="0" y="0" width="10" height="10" style="fill:#f00;"/>
+    </pattern>
+    <symbol id="testsymbol">
+        <rect x="0" y="0" width="10" height="10" style="fill:#0f0;"/>
+    </symbol>
+  </defs>
+  <defs id="defs_two">
+  </defs>
+  <defs id="defs_three"/>
+</svg>