Can't find stored procedure - help!

[db2user24]

I'm trying to invoke a DB2 stored procedure. The stored proc is coded
in C and compiled to a shared library, which has been placed in the
<DB2 dir>/functions directory. The platform is Linux (using 64 bit DB2 UDB).
From the debug log it seems that the stored procedure can't be found,
although I don't know why. I can see that the procedure name is defined in the database, however it can not be invoked.
Can anyone shed any light on what could be causing this problem, or
suggest anything for further investigation?

Here is the output :

2007-12-07-23.49.45.651049+000 I12584724E396 LEVEL: Severe
PID : 7075 TID : 47586765438720PROC : db2fmp
INSTANCE: db2inst1 NODE : 000
FUNCTION: DB2 UDB, routine_infrastructure, sqlerRoutineResolveAddress, probe:10
RETCODE : ZRC=0x870F0038=-2029060040=SQLO_PROC_NOT_FOUND "Stored Proc Not Found"
DIA1002C Error accessing function "" in library "".

2007-12-07-23.49.45.651595+000 E12585121G592 LEVEL: Error (OS)
PID : 7077 TID : 4138646016 PROC : db2fmp32
INSTANCE: db2inst1 NODE : 000
FUNCTION: DB2 UDB, oper system services, sqloLoadModule, probe:190
CALLED : OS, -, dlopen OSERR: EILSEQ (84)
DATA #1 : Library name or path, 41 bytes
/home/db2inst1/sqllib/function/RCheck
DATA #2 : shared library load flags, PD_TYPE_LOAD_FLAGS, 4 bytes
0
DATA #3 : String, 100 bytes
/home/db2inst1/sqllib/function/RCheck: cannot open shared object file: No such file or directory

2007-12-07-23.49.45.652163+000 I12585714E396 LEVEL: Severe
PID : 7075 TID : 47586765438720PROC : db2fmp
INSTANCE: db2inst1 NODE : 000
FUNCTION: DB2 UDB, routine_infrastructure, sqlerRoutineResolveAddress, probe:10
RETCODE : ZRC=0x870F0038=-2029060040=SQLO_PROC_NOT_FOUND "Stored Proc Not Found"
DIA1002C Error accessing function "" in library "".

2007-12-07-23.49.45.652383+000 E12586111G592 LEVEL: Error (OS)
PID : 7077 TID : 4138646016 PROC : db2fmp32
INSTANCE: db2inst1 NODE : 000
FUNCTION: DB2 UDB, oper system services, sqloLoadModule, probe:190
CALLED : OS, -, dlopen OSERR: EILSEQ (84)
DATA #1 : Library name or path, 41 bytes
/home/db2inst1/sqllib/function/RCheck
DATA #2 : shared library load flags, PD_TYPE_LOAD_FLAGS, 4 bytes
0
DATA #3 : String, 100 bytes
/home/db2inst1/sqllib/function/RCheck: cannot open shared object file: No such file or directory