smoke help

I have an 88 gt with about 125,000 miles on it, when i "ride" a gear down, lets say like 2nd gear from 3500 rpm's and down i will get a puff of smoke out of the tail pipes, its blue so its oil, i was just wondering if that could be the valve seals in the heads. please, any help is greatly appreciated.
please email me and post a thread if possible. computer is real slow on this site

thanks

Nick

skeezo83@hotmail.com