Does siteminder 12.0 sp3 agents supports apache 2.4 on RHEL 5.11?
No, Its not supported.
Platform Support Matrix
R12 : SAP Portal Services
R12.52 : SAP Portal Services
R12.51 : SAP Portal Services
None of this SM 12.0,12.51,12.52 agents supports apache 2.4 version, then which version of siteminder does 2.4 is supported?
Apache 2.4 is supported on Redhat 6,7 on 12.52 / 12.51 webagents . Not on Redhat 5 .
Refer above Platform Support Matrix.
Could you please double check that 12.51 supports apache 2.4 64 bit on RHEL 6? Because I didn't see any thing with 2.4 apache in Supported Matrix sheet for 12.51.
Refer : 5. 64-BIT WEB AGENTS
12.51 64 web agent supported on Apache 2.4.x on Red Hat 6(64-bit) .