vsftpd: install pam_pwdfile on CentOS with yum?

Question

I'm trying to get VSFTPD to work with a virtual user so that I can just login to any directory with a user I define.

Unfortunately I get the following error when trying PAM with VSFTPD:

PAM [error: /lib/security/pam_pwdfile.so: cannot open shared object file: No such file or directory]

pam_pwdfile doesn't seem to be available in YUM or centos, does anyone know how I can still use this?

Or are there alternative ways to just say to VSFTPD:

user1 -> ftp directory /var/www/user1 user2 -> ftp directory /var/www/somethingelse