Here's the skill substitution guide from the old WotC forums: [There was a link here, but I can't post it because I don't have enough posts on this forum to do it. If you want it I can try to PM it to you]
Might be useful. You could use a wisdom based skill (Nature in this case) for Diplomacy and Bluff through taking both the level 2 utility powers Arcane Mutterings and All-Encompassing Nature. Probably the most useful would be taking All-Encompassing Nature normally at level 2 through being a Druid, and Arcane Mutterings through the Skill Power feat. As a bonus this would also allow you to use Intimidate, Dungeoneering, Arcana and Religion through Nature once per encounter.