What is the location of the directory of C header files that match your running kernel? [/usr/src/linux/include] /usr/src/kernels/2.6.18-53.el5-i686/include
The directory of kernel headers (version 2.6.18-53.el5) does not match your running kernel (version 2.6.18-53.1.13.el5xen). Even if the module were to compile successfully, it would not load into the running kernel.
version 2.6.18-53.1.13.el5xen を要求しているように見えるのですが、そんなものはマシンの中に見当たりません・・・。