cast numeric to char

Howdy:

Running PostgreSQL 7.2.1 -

I'm trying to cast a numeric field to character, but I
am getting errors saying that it can not be done.

[snip errors]

testdb=> select lpad(i_pd::char,7,'0') from t_table limit 1;
ERROR: Cannot cast type 'numeric' to 'character'

[/snip error]

Is it that I *can not* cast numeric into character value or
or do I need some new methodology of doing this?

Thanks!

-X