Lens inside dirty

Hello,
Unfortunately you would need to strip the lens completely to get to all glass elements inside to clean them. This is fairly fiddly operation and although I rate TZ3 lens as one of the easiest to dismantle I wouldn't recommend it unless you're really really comfortable with fiddly stuff. Actually, it's easy to take apart-putting it back together is more tricky - I learned the hard way :)
I would suggest getting a TZ3 with e.g. a broken screen from ebay and use it as a donor to get working lens and replace the one on yours.
Unfortunately I don't think there's an easy way to fix this.
Good luck,
Raf

Well... The service manual is here:

http://tsn.pasc.panasonic.com/viewing/ALL/DMC-TZ3P/SVC/DSC0703019CE_PRINTB/DSC0703019CE.pdf

before you do it, can I suggest popping the end of a shop vac over the lense as it is pulled out and seeing if that helps at all? It probably won't but it's a lot easier than pulling this to pieces, especially since the lense is not that accessible.

I wish you luck, it's not a fun task!