[courier-users] Authentication problem

[zafar]

hello sir        i face a problem using courier-imap bcz courier-imapis authenticate the users. i compile pakcage as this ./configure make make check and others default action. and it install successfully and give me no error except one. which is that ------------- /usr/bin/ld: cannot find -lvpopmail collect2: ld returned 1 exit status make[1]: *** [authvchkpw] Error 1 make[1]: Leaving directory `/home/zafar/courier-imap-1.4.1/authlib' make: *** [all-recursive] Error 1 ----------------   the other steps are compiled fine. but when i test it with telnet 0 143 it give me welcome message and then i give him the username and password but it not authenticate the users. i can't understand the problem.   plz guide me what i do to check it bcz before i install it as it is ,and its work fine till but that server is creating problems .   so guide me thanks zafar