or $error .= "Illegal customer number " . $param->{"custnum"} . " ";
my $custnum = $1;
-$param->{"amount"} =~ /^\s*(\d+(\.\d{1,2})?)\s*$/
+$param->{"amount"} =~ /^\s*(\d*(?:\.?\d{1,2}))\s*$/
or $error .= "Illegal amount " . $param->{"amount"} . " ";
my $amount = $1;