Something

Index: src/game/SpellMgr.cpp
===================================================================
--- src/game/SpellMgr.cpp	(revision 5056)
+++ src/game/SpellMgr.cpp	(working copy)
@@ -788,6 +788,13 @@
     if(spellInfo_2->SpellFamilyFlags == 2048)
         return false;
 
+	// Rend and Deep Wound
+    if( spellInfo_1->SpellFamilyName == SPELLFAMILY_WARRIOR &&
+        spellInfo_2->SpellFamilyName == SPELLFAMILY_WARRIOR &&
+      ((spellInfo_1->SpellIconID == 243 && spellInfo_2->SpellIconID == 245) ||
+       (spellInfo_1->SpellIconID == 245 && spellInfo_2->SpellIconID == 243) ))
+        return false;
+
     // Resurrection sickness
     if((spellInfo_1->Id == 15007) != (spellInfo_2->Id==15007))
         return false;