CURSORs and selects with parameters

When using cursors through the libpq interface, do I need to be
passing in the parameters when I'm FETCHing from them?

I've got some code that uses PQexecParams and does the equivalent of:

    DECLARE a_cursor CURSOR FOR SELECT foo, bar FROM baz WHERE field = $1
    FETCH NEXT a_cursor

but when I get to the FETCH I'm getting back the error:

    ERROR:  no value found for parameter 1

which is fair enough, as I'm not *passing* in any parameters to the
fetch. (Yes, I double-checked--the parameter count in the
PQexecParams call is 1 for the cursor declaration, and 0 for the
fetch) Do I have to?
--
                Dan

--------------------------------------it's like this-------------------
Dan Sugalski                          even samurai
dan@sidhe.org                         have teddy bears and even
                                       teddy bears get drunk