Import .obj into Maya 2008 (32 bits)
OBJ file must be converted to OGRE Mesh format. To achieve this, the current best documented methodology is to use Maya and its OGRE exporter. All other route seems to require production of MESH.XML which takes another extra step to produce MESH and so far have not produced very good result. Hence, it is RECOMMENDED to use Maya's Mesh exporter.
First make sure you have installed Maya OGRE exporter.
Then you need to open OBJ into Maya using the IMPORT option in Maya. Once imported, and maya exporter already installed, you can just click on the OGRE menu item and hit proceed with the export process. Make sure you specifies the DIRECTORY and the FILE NAME of the MESH file that you are trying the export. So far, I have not explored too much into how to export material and skeletons etc. I am mainly focused on getting the structural information.
Post Export Processing
This is a simple alignment process. Once you acquired MESH file, you can directly import into realxtend already but the end result is usually with a large displacement.
To fix that issue, realxtend developers have released a very powerful and simple tool that fix the issue called rexTool. You may be able to get a copy of this from here