The BT3030 bluetooth headset is a nice headset but with the iphone the minimum volume is too high.
It seems that a firmware update on the jabra can help a bit.
See http://discussions.apple.com/thread.jspa?threadID=2064373 for the discussion but in brief:
I have no idea how they are finding the links to the firmware (can't read japanese) - so the apple thread is my only source of info.
Note - I did have to re-pair the iphone and bt3030 after the update. But that worked and now volume is much better
Update on AVRCP
As noted in the comments below - from iOS 4.1 the AVRCP version was updated allowing for next/prev and ff/rw. See also iPhone 3.0 firmware release and stereo bluetooth - it does support AVRCP - just not all of it