These are admittedly not pretty (or condensed as much as they could be), but they work:
http://www.jennandmatt.com/misc/bagle/
On a post formatting note: is there any way I'm missing to do something similar to <pre> tags in a post? I couldn't get the rules to format correctly inline, hence the URL.
-Matt
<[a-z]{19}@
What you want is <ecode>.
header BAGLE_WORM_SUBJ1 Subject =~/E-?mail account (security|utilization|disabling) warning\./
describe BAGLE_WORM_SUBJ1 Virus - Appears to be the W32/Bagle.j@MM worm
score BAGLE_WORM_SUBJ1 5
header BAGLE_WORM_SUBJ2 Subject =~/((Important )?[Nn]otify|Warning) (about your|(about )?using the) e-mail account( utilization)?/
describe BAGLE_WORM_SUBJ2 Virus - Appears to be the W32/Bagle.j@MM worm
score BAGLE_WORM_SUBJ2 5