Sometimes, you can get the following error on VPS while running easy apache. You can fix by simple following steps.
Login in to main VPS and edit the variable PRIVVMPAGES accordingly
/scripts/easyapache
Use of uninitialized value in pattern match (m//) at /var/cpanel/perl/easy/Cpanel/Easy/Utils.pm line 436.
!! Critical Error (VZ): You are only only allowed to use 90 Megabytes of ram! 512 Megabytes is required. !!
You can also modify the privvmpages values from shell as required. (For OpenVZ users) :
vzctl set 101 --privvmpages 850M:900M --save