arcSDE support for ms4w

[krishna S]

Hello all,
      I installed ms4w mapserver and its working fine. I want to make a
connection with ARCSDE so i installed ARCSDE 9.1 client APIs. When i
include the connection steps in the mapfile i get the following error

=======================================================================
Warning: [MapServer Error]: msSDELayerOpen(): SDE support is not available.
in C:\ms4w\Apache\htdocs\mapserverdata\test.php on line xx

Fatal error: Call to a member function on a non-object in
C:\ms4w\Apache\htdocs\mapserverdata\test.php on line xx
 ==========================================================================

I am not sure about the cause of this error. Does ms4w support ARCSDE, if
so can anyone please tell me how to compile it to make ARCSDE work. If MS4W
does not support arcsde can you suggest some other version of mapserver
which is available (Please provide the link ....)

Thanks for all your help ....