How to Customise SquirrelMail

SquirrelMail version 1.4.13
By the SquirrelMail Project Team
ERROR
Unknown user or password incorrect.
Go to the login page

I would like to customise the above message when there is a login error during webmail login. What file should I edit?. Please help me

See you

squirrelmail failes located at ehcp/webmail folder.
Please have a look at squirrelmail resources, documents, on its site.
i am not sure howto replace that messsage.

to login properly in squirrelmail, use fully: username@yourdomain.com