I lost the script that I used to use to convert mac line endings (returns) to unix line endings (new lines), so I did a search on the web to see what scripts I could find.
There are a lot of implementations of this script. Some using perl, shell script or the flip program. The one that I like to use is an alias in my .bashrc. I found this at macosxhints.
alias mac2unix="perl -pi -e 's/rn?/n/g' "