The issue is that a 64 bit version of Siteminder is being integrated with CA Arcot using a 32 -bit version of CA Arcot binary - libArcotSiteMinderAdapter.so. This can happen when the new CA Adapter installer has not been run on the new 64-bit Siteminder server. Essentially ,the required files have been copied straight from a 32-bit server to the new 64-bit server. This leads to the discrepancy.
CA Siteminder Policy Server running on Linux
Mismatch between CA Siteminder and CA Arcot Adapter binaries with respect to architecture (64-bit versus 32-bit).