using eregi - what regular expression rules does it use ? works in linux ( grep ) but not PHP - help needed

There not much documentation in the online manual about eregi. Apart from the usage I need to know more about what regx it uses, in the linux shell , using grep i got it right for my needs .. I want to find and reject content with email address .. [desiredating@opie desiredating]$ echo "neil@some.com" | grep "@*\." neil@some.com [desiredating@opie desiredating]$ echo "meet me @ 8" | grep "@*\." ----------- the above is correct and fine , but see below , it doesnt work in php ( the same regular expression doesnt ) if (eregi("@.\.",$about_me)) { include "error_msg/error_email_in_profile.php"; $error =1 ; } -------- What regular expression do i neep to use , is there any reference out there to tell me ? Urls / info is greatly appreciatted. Thanks in advance !! Neil -- Totally FREE dating site. FREE all-inclusive lifetime membership when you join today Meet and date new people. Thousands of members looking for someone like you == http://www.desiredating.com = Join FREE today, you have nothing to lose