I would recommend reposting this in the Security forums.
I'm having a hard time deciphering your problem because I believe you misspelled some words...
"i am able to ping any IP address apart from the 3 DMZ interfaces"
"i can ping nodes attached to these interfaces"
"i can ping the inside interface"
Which one of these is really the problem?
Take your time and try to post clear problem descriptions - you will get more responses.
Cheers.