It is a bug in RFB which was fixed with the newer versions which only run with 1.5.
I'm using 1.4 too and removed all torpedo entries from the RFB library.
I replaced them then with the realistic torpedo malfunctions mod of NSM.
Works fine here.
http://files.filefront.com/NSM4+Real.../fileinfo.html
But before you do anything you might want to wait until someone replies who really knows something about it. I just did a lot of patchwork here and it is quite possible that there is a simpler solution.