Internal Server Error 500 No response from subprocess (php): subprocess was killed with signal 25

Hi guys,

Everything was working fine yesterday but suddenly I started to get this error when trying to access Roundcube with all emails. After putting the credentials and trying to go to the inbox this error shows up:

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Internal Server Error

500

No response from subprocess (php): subprocess was killed with signal 25
cpsrvd/11.42.1.23 Server at *domain*
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I found a similar post in here: http://forums.cpanel.net/f5/internal-server-error-500-no-response-subprocess-php-subprocess-killed-signal-11-a-383962.html

But I tried all the ideas in there and still got the same error. Tried upgrading cPanel, restarting IMAP, restarting the vps...

I think it might have something to do with the daily cPanel upgrade, since it started appearing from one day to another. I wondered if I could downgrade it to see if that was the problem, but I don't know how.

Any ideas?

Thanks in advance.