The amd64 packages are not actually compiled for amd64: /usr/lib/smlnj/bin/.run/run.x86-linux: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=205158fc8f5bd70fe18a4b1f2a5279e01053b961, stripped This means that they cannot run on systems where the kernel does not provide the i386 system call interface.
Control: severity -1 wishlist Control: tag -1 upstream Control: retitle -1 Provide 64-bit binaries Yes. That's why smlnj-runtime Depends on libc6-i386. Upstream doesn't have native 64-bit support yet. That's not a typical configuration. If you're going to disable support for the 32-bit interface, then you'll have to wait until upstream finishes 64-bit support. Cheers, James
* James McCoy: These days, users could just install the smlnj:i386 packages, which would makes this much more explicit.