[SOLVED] sahi - ERROR missing ( before function parameters

i was sahi testing the following function:

function do_must_change_password($invalid_security_policy_password, $valid_security_policy_password) {
    _setValue(_password("changePwForm:currentpassword"), $invalid_security_policy_password);
    _setValue(_password("changePwForm:newpassword"), $valid_security_policy_password);
    _setValue(_password("changePwForm:confirmnewpassword"), $valid_security_policy_password);
    _click(_button("changePwForm:changePwBtn"));
}

but sahi was throwing this error on the line highlighted in red:
ERROR
missing ( before function parameters.

i found out that you can't end a sahi function name with _password, so i had to change the function name to:
function do_must_change_pwd(...

and then it worked :)

i've noticed that this also applies to function names ending in:
_list
_file

UPDATE: it looks like this might be the list of function name restrictions:
sahi/config/normal_functions.txt