yes, it changed the glibc. 
you can try using this version of the vm, it should work: 

http://files.pharo.org/vm/pharo/linux/pharovm-u804.tar.gz

Esteban

On 22 Apr 2014, at 01:15, Sergi Reyner <sergi.reyner@gmail.com> wrote:

2014-04-21 23:12 GMT+01:00 GABRIEL DEFAGOT <gaby_defa91@hotmail.com>:
/pharo3.0/bin/pharo: /lib32/libc.so.6: version `GLIBC_2.15' not found (required by /pharo3.0/bin/pharo)

What's missing?

A newer version of glibc, probably. Ubuntu 12.04 has glibc-2.15.

Cheers,
Sergi