Toad for DB2 z/OS Use of SYSDUMMY1 Table (4274949)

I created the following statement in an edit window.

SELECT LENGTH('123456789 ')
from SYSIBM.SYSDUMMY1;

When I execute it, it returns 13 (and so it should)

However,

If I change the statement and add a parameter, like so;

SELECT LENGTH(:NUMVAR)
from SYSIBM.SYSDUMMY1;

and I execute it (when the parm window pops up, I enter the same value as the original statement, defined as VARCHAR or CHAR) and I get the following error;

Lookup Error - DB2 Database Error: ERROR [42610] [IBM][DB2] SQL0418N A statement contains a use of an untyped parameter marker, the DEFAULT keyword, or a null value that is not valid.

WORKAROUND:
In this example use the following statement:

select LENGTH (CAST(:numvar AS VARCHAR(55))) from SYSIBM.SYSDUMMY1;

STATUS:
Waiting for fix in a future version of Toad for DB2