Cron + PHP Error

I have a cron script. It was working fine until few days ago.

When i use this cron command:

curl http://example.com/cron.php

Code (markup):

I got "500 internal server" error as the result.

When i use this cron command instead

php /www/dir1/dir2/abs_path_etc/cron.php

Code (markup):

I got "MySQL server has gone away" message.
It just a simple SQL query, less than 150 characters, just updating some rows.

Does mysql connection can not be used on the second cron command?

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check your error log from cpanel and let us know !

 

Here is my common error log -- taken from cpanel

[Tue Jan 27 05:03:01 2009] [error] [client 74.53.*.*] File does not exist: /{path}/public_html/osyt.com/500.shtml
[Tue Jan 27 04:50:02 2009] [error] [client 195.194.*.*] File does not exist: /{path}/public_html/osyt.com/favicon.ico

Code (markup):

 

try one of those
php /www/dir1/dir2/abs_path_etc/cron.php /dev/null 2>&1
php -f /www/dir1/dir2/abs_path_etc/cron.php /dev/null 2>&1
php -g /www/dir1/dir2/abs_path_etc/cron.php /dev/null 2>&1
wget /www/dir1/dir2/abs_path_etc/cron.php /dev/null 2>&1

 

Thanks for the tips
I'll try some of them.