Error deleting accounts

[dg1]

Clicking on red delete button fails, error:

Code Select Expand

Notice: Undefined variable: ssh_exec in /usr/local/cwpsrv/htdocs/resources/admin/modules/list_accounts.php on line 0

Fatal error: Function name must be a string in /usr/local/cwpsrv/htdocs/resources/admin/modules/list_accounts.php on line 0

Any ideas?