I hate to be an echo, but I too am having the same problem.
I ran the magento-check.php on my new Reseller hosting account and got this message (below).
You can see, it failed on MySQL (I haven’t installed a database yet, I only set up the hosting earlier today) and mcrypt. I have emailed Fasthosts support who claim mcrypt is disabled for security and performance reasons. Still playing email tennis with them, trying to find out my options. I’m not sure if I should be concerned that mhash isn’t on here - I’ve read about Fasthosts not allowing mhash and mcrypt, so why am I not getting mhash in this error message? Do they allow it now perhaps?
If anyone has an answer for this problem (that isn’t move from Fasthosts), I’d be very eager to hear about it.
Warning: shell_exec() has been disabled for security reasons in /home/fhlinux193/o/~removed~/user/htdocs/magento-check.php on line 28
Your server does not meet the following requirements in order to install Magento.
The following requirements failed, please contact your hosting provider in order to receive assistance with meeting the system requirements for Magento:
* You need MySQL 4.1.20 (or greater)
* You are missing the mcrypt extension
The following requirements were successfully met:
* You have PHP 5.2.0 (or greater)
* Safe Mode is off
* You have the curl extension
* You have the dom extension
* You have the gd extension
* You have the hash extension
* You have the iconv extension
* You have the pcre extension
* You have the pdo extension
* You have the pdo_mysql extension
* You have the simplexml extension