diff --git a/yum/depsolve.py b/yum/depsolve.py
index ad47a1d..1c65621 100644
--- a/yum/depsolve.py
+++ b/yum/depsolve.py
@@ -492,32 +492,14 @@ class Depsolve(object):
         thisarch = requiringPo.arch
         newest = provSack.returnNewestByNameArch()
         if len(newest) > 1: # there's no way this can be zero
+                            
             best = newest[0]
-            for po in newest[1:]:
-                if thisarch != 'noarch':
-                    best_dist = archDifference(thisarch, best.arch)
-                    if isMultiLibArch(): # only go to the next one if we're multilib - i686 can satisfy i386 deps
-                        if best_dist == 0: # can't really use best's arch anyway...
-                            best = po # just try the next one - can't be much worse
-                            continue
+            old_best = None
+            while best != old_best:
+                old_best = best
+                best = self._compare_providers(newest, best, thisarch)
+                    
                 
-                    po_dist = archDifference(thisarch, po.arch)
-                    if po_dist > 0 and best_dist > po_dist:
-                        best = po
-                        continue
-                        
-                    if best_dist == po_dist:
-                        if len(po.name) < len(best.name):
-                            best=po
-                            continue
-                            
-                elif len(po.name) < len(best.name):
-                    best = po
-                elif len(po.name) == len(best.name):
-                    # compare arch
-                    arch = rpmUtils.arch.getBestArchFromList([po.arch, best.arch])
-                    if arch == po.arch:
-                        best = po
         elif len(newest) == 1:
             best = newest[0]
         
@@ -922,6 +904,48 @@ class Depsolve(object):
         return installed
     _isPackageInstalled = isPackageInstalled
 
+    def _compare_providers(self, pkgs, bestpkg, requiring_arch):
+
+        for po in pkgs:
+            if po == bestpkg: # if we're comparing the same one, skip it
+                continue
+                
+            obsoleted = False
+            for obs in po.obsoletes:
+                if bestpkg.inPrcoRange('provides', obs):
+                    return po
+
+            # make sure the best doesn't obsolete this po - if it does we're done
+            # we do this b/c it is possible for two entries to oscillate in this
+            # test - obsolete should trump no matter what
+            # NOTE: mutually obsoleting providers is completely and utterly doom
+            for obs in bestpkg.obsoletes:
+                if po.inPrcoRange('provides', obs):
+                    return bestpkg
+                    
+            if requiring_arch != 'noarch':
+                best_dist = archDifference(requiring_arch, bestpkg.arch)
+                if isMultiLibArch(): # only go to the next one if we're multilib - i686 can satisfy i386 deps
+                    if best_dist == 0: # can't really use best's arch anyway...
+                        return po # just try the next one - can't be much worse
+
+            
+                po_dist = archDifference(requiring_arch, po.arch)
+                if po_dist > 0 and best_dist > po_dist:
+                    return po
+                    
+                if best_dist == po_dist:
+                    if len(po.name) < len(bestpkg.name):
+                        return po
+                        
+            elif len(po.name) < len(bestpkg.name):
+                return po
+            elif len(po.name) == len(bestpkg.name):
+                # compare arch
+                arch = rpmUtils.arch.getBestArchFromList([po.arch, bestpkg.arch])
+                if arch == po.arch:
+                    return po
+
 
 class DepCheck(object):
     """object that YumDepsolver uses to see what things are needed to close
diff --git a/yum/packages.py b/yum/packages.py
index 2a650f0..48fd524 100644
--- a/yum/packages.py
+++ b/yum/packages.py
@@ -247,6 +247,8 @@ class RpmBase(object):
         return False
 
     def __ne__(self, other):
+        if not other:
+            return True
         if comparePoEVR(self, other) != 0 or self.arch != other.arch or self.name != other.name:
             return True
         return False