Piki, first of all thanks for your offer to contribute to this project.
Porting openmamba to the x86_64 architecture requires first some not trivial work on the gcc/glibc toolchain, and having or getting experience on this would be necessary. The x86_64 glibc is available for cross-compilation (package is cross-x86_64 glibc) and one of the first things to do would be creating multilib (x86 and x86_64) glibc for the x86_64. If you are interested in this development, I can provide a x86_64 kernel build and I would suggest you to subscribe to the openmamba-devel (english language) mailing list (see http://www.openmamba.org/lists/) for further discussion.
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