rsh problem in ksh

On a SUN cluster (ksh - Solaris 8 SPARC) I run a script which at some time has to perform a rsh command on the alternate node but with some other user (let's say "oper") so it should be like:

rsh su - oper -c APP_COMMAND -paramters

When I run the script APP_COMMAND is done but without taking into account the parameters I gave.
It's not what I want because it generates a lot of output...

What it happend? How can be fixed this?
There is a problem with the environment, can I do something - anyway it's not my task and I'm not allowed to configure it!

Interesting is the fact that when I run a system command:

rsh su - oper -c df -k

the parameters work just fine.

Meanwhile locally it works just fine on both nodes:

su - oper -c APP_COMMAND -paramters

Thank you for your help...

rsh su - oper -c "APP_COMMAND -paramters"

Sorry I have misstyped 'coz I was really rushing...

Obviously I used inside the script for local node - node1:

su - oper -c "APP_COMMAND -paramters"

Meanwhile on node2:

rlogin node2 su - oper -c "APP_COMMAND -paramters"

On node1 the application command is executed correctly.
On node2 the application command is executed without taking into account the option -parameters.

I might have differences between the environments of the nodes (I am not allowed to change them). Does anyone have an idea?