Calling an occurrence operation with parameter(s) fails with retrieve/a

Summary:
When an occurrence operation with parameter(s) is called in the context of a
retrieve/a instruction then this will fail with the error -1122 (Wrong number
of arguments). When the operation has no parameter then the call works fine.

Symptoms:
When an occurrence operation with parameter(s) is called in the context of a
retrieve/a instruction then this will fail with the error -1122 (Wrong number
of arguments). When the operation has no parameter then the call seems to work
fine.

Consider the following scenario:

• The form FRM1 has the entity ENT1 painted
• In the Occurrence operations trigger of ENT1 the operation
  occOper1Ent1 is defined with one parameter
• In the Read trigger the occurrence operation occOperEnt1 is
  called; e.g.

read
if ($status >= 0)
vStatus = $occHandle->occOper1Ent1("Process")
endif
return($status)

• In the Exec trigger of FRM1 the following code is executed:

FLD1.ENT1/init = "ABC"
retrieve/e "ENT1"

creocc "ENT1", -1
FLD1.ENT1/init = "XYZ"
retrieve/a "ENT1"

Result: when the Read trigger is fired by retrieve/e then
all the calls of the occurrence operation occOper1Ent1 are successful,
but when the Read trigger is fired by retrieve/a (retrieve additional
occurrences without discarding the hitlist) then all the calls of the
occurrence operation occOper1Ent1 will fail with the error
-1122 - Wrong number of arguments.

The problem does not occur when the occurrence operation has
no parameters defined.