diff -r 7c5adf8e29eb -r 68c51e98aed8 AMBuildScript
--- a/AMBuildScript	Sun Mar 11 18:07:24 2012 -0500
+++ b/AMBuildScript	Wed Mar 21 21:25:34 2012 -0500
@@ -80,8 +80,9 @@
 						oldhead = head
 						head, tail = os.path.split(head)
 					if i.startswith('HL2SDK'):
-						(info, sdk) = findDictByKey(self.possibleSdks, 'sdk', i)
-						self.sdkInfo[sdk] = info	
+						if head != None and head != oldhead:
+							(info, sdk) = findDictByKey(self.possibleSdks, 'sdk', i)
+							self.sdkInfo[sdk] = info
 					elif head == None or head == oldhead:
 						raise Exception('Could not find a valid path for {0}'.format(i))
 				AMBuild.cache.CacheVariable(i, path)