Duplicate calendars on iphone after move to new imac. Sync via mobile me

Just migrated to a new imac from imac G5 using the Time machine function: worked like a charm except a few tweaks: prefs changing in itunes relating to iphone sync.

Noteworthy is the fact i sync my desktop calendar over the air with mobile me.

I now have 2 sets of calendars on my iphone: one called "on my iphone" and the other ".mac account (mobile me)". The latter behaves as it should: it syncs flawlessly. The other set corresponds to the state of my calendars when I first synced with itunes on my new Imac... useless space wasting info!

My question is: How do I get rid of this redundant and outdated set of calendars???

Can't see any function to do so in either iphone or itunes. Calendar syncing is not checked (since syncing happens via mobile me...)

Any help or solution greatly appreciated!!