如何在preg_match中允许utf-8字符集？

I am using preg_match() function only to allow specific charachters to accept. It is allowing all alphabates and numbers but along with that i also want to allow utf-8 characters such as "ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ" so how can i allow this charachters from preg_match() function.Plase suggest me. Thanks in advance.

Regards

Shri

Try the /u pattern modifier to let the PCRE engine know you're using UTF-8 patterns:

This modifier turns on additional functionality of PCRE that is incompatible with Perl. Pattern strings are treated as UTF-8. This modifier is available from PHP 4.1.0 or greater on Unix and from PHP 4.2.3 on win32. UTF-8 validity of the pattern is checked since PHP 4.3.5.