I have talked with him. Every thing works fine, until he changes the one string (sent by reference). We have walked through his code and know that it is when He puts the new string in that memory location that the error occurs.
here is my code for this:

lcNullTerminator = ""
DECLARE INTEGER CreateEdulogRun IN edulogdll STRING @, STRING @, STRING @,;
STRING @, STRING @, STRING @
*!* EDULOGDLL_API int CreateEdulogRun(char *RunID, char *RouteID, char *Description, char *AMPMFlag,
*!* char *CreateDate, char *EndDate);
< snip error check code >

lcRunID = padr(ALLTRIM(laFields[6]) + lcNullTerminator,12, " ")
lcRouteID = padr(ALLTRIM(laFields[7]) + lcNullTerminator,11, " ")
lcAMorPM = IIF(laFields[8], "1", "0") + lcNullTerminator
lcDescrip = ALLTRIM(laFields[9]) + lcNullTerminator
lcCreateDate = ALLTRIM(laFields[10]) + lcNullTerminator
lcEndDate = ALLTRIM(laFields[11]) + lcNullTerminator
*!* check to be sure there is a run and route id
IF !EMPTY(laFields[6])
--> lnReturnvalue = CreateEdulogRun(@lcRunID, @lcRouteID, @lcDescrip, ;
@lcAMorPM, @lcCreateDate, @lcEndDate)

at the --> is where the error occurs in my code. His code does fine until he does a copy command into the memory location of lcRunID.

any ideas?