sql function call

Hello,

I'm trying to call the builtin sql function CURRENT_TIMESTAMP since I want
to use the database's concept of now, not LW's.  I get as far as:

(sql:select (sql:sql-operation 'function "CURRENT_TIMESTAMP"))

Error: Non-object field(s) in object select -- (#<SQL-VALUE-EXP
"CURRENT_TIMESTAMP()">)
 >>> (#<SQL-VALUE-EXP "CURRENT_TIMESTAMP()">) <<<
  1 (abort) Return to level 0.
  2 Return to top loop level 0.

the expression SELECT CURRENT_TIMESTAMP; should be valid SQL99 syntax
assuming my database supports that function.