No, the JPEG license is pretty benign, and the features you have added are well worth the code inclusion if it's needed. I'm a bit doubtful that it was a good idea to include new code in a working codepath before 7.5, but that is between me and Nilsson and nothing you need to feel guilty about.
I have a suggestion though: Anyone cut-ing and pasting code should mark the affected areas in the code. with a begin and an end comment if it would be needed to revert it for some reason at a later date. The same for code inspired by other code to the degree where the code can be said to be based on the original in the copyright sense of the word.
/ Peter Bortas
Previous text:
2002-10-07 09:06: Subject: Copyright
Is it so bad? I used some of the jpegtran code for lossless image flipping/rotation in the Image.JPEG source. We can always revert it...
/ M Norrby (rabies), Shapeline