Help with Mail - crashes on use of Edit button

[hnsnash]

Hi, I am new here so would appreciate help.

have iPad2 (IOS 5.1.1) and have recent problem (never HAD issue before). Whenever I hit Edit button to be able to select mails for deletion from mailboxes etc., the App simply closes.

Have tried reset, etc and can delete via swiping each message but too many mails to keep doing that

Any ideas on what problem is and how to fix ?