How to delete these flooded files?

we have ORACLE database 11.1, Solaris 10.10, database audit is turned on, there are flooded amount of *.aud files under adump directory, we need keep them for 30 days, then delete them.

but the problem is use this command "find .  -name "*.aud" -mtime 30  -print -exec rm -f {} \; "      does not work, because too many files

adump> ls -l |wc -l
2877939

rm *.aud
-bash: /usr/bin/rm: Arg list too long

any idea ?

Thanks,