Belgium doesn't want their APC's back. This "theft" is cover for their backing of certain African tyrants ( read here for FR background on Equitorial Guinnea, France, and Joe Wilson's ex-wife Jaqueline Wilson's involvement).
Belgium had received great flak for selling arms to African tyrants in the recent past (see here: http://www.iansa.org/documents/development/undermining_development.htm , and here: http://www.pbs.org/frontlineworld/stories/sierraleone/bout.html , and here: http://www.expatica.com/source/site_article.asp?channel_id=3&story_id=20724 )...now they've found a way to get the arms there without suffering political damage...simply pretend that their weapons were stolen.