...and also put your sample data in code tags, too. This way people have a chance at reproducing the problem.

I added strict & warnings and put in the required declarations. But when I gave it your rules file, it just printed a couple warnings (because it tried to use undefined values as numbers) and then stopped without doing anything, like so:

Header:
1) icmp rule alert icmp $EXTERNAL_NET any -> $HOME_NET any
Use of uninitialized value $minLength in multiplication (*) at 1135963
+.pl line 78, <DATA> line 1.
Use of uninitialized value $maxLength in multiplication (*) at 1135963
+.pl line 78, <DATA> line 1.

 Wrote 0 patterns to file: "UNSPECIFIED"
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Because I can't trust the sample data, and can't read your code with the hideous indenting, that's all the further I cared to go to try to find what your problem might be.

Update: fixed cut & paste error (left off final line of output) and rephrased a bit for clarity.

...roboticus

When your only tool is a hammer, all problems look like your thumb.