==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.5-1
- Linux/BSD distribution name and version: Red Hat Enterprise Linux Server release 6.7 (Santiago)
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro?
- Related log if you're reporting an issue:
====

Attempt to log into roundcube results in 500 error.
Looking in the maillog I see the following error:

Aug 10 09:40:43   roundcube: PHP Fatal error:  Call to undefined function mb_strtolower() in /var/www/roundcubemail-1.2.0/progra$

from what I can tell this probably means PHP needs to be recompiled with --enable-mbstring.  When I look up the running of configure there can be quite a few options to specify (file locations for apache, mysql config file, etc...)

Is there a redmail recommended command for running configure to get all the correct paths?

Appreciate any help that can be provided.