drupal error: cannot instantiate xmlrpc_client (cron)

[Erik Steffl <steffl@bigfoot.com>]

since latest upgrade of drupal I get the following error from Cron 
<www-data@jojda>          [ -x /usr/share/drupal/scripts/cron.sh ] && 
/usr/share/drupal/scripts/cron.sh:

Fatal error: Cannot instantiate non-existent class:  xmlrpc_client in 
/usr/share/drupal/modules/drupal.module on line 142

  I suspect it has something to do with the xmlrpc security fix, 
anybody else seen it? Just asking before filing a bug report (don't want 
to file a bug report if it's something wrong on my end).

  BTW the error is in function that tries to ping the drupal directory 
server.

  TIA,

	erik