Here's some more information from the great Michael Jackson: http://www.beerhunter.com/documents/19133-000195.html
. Apparently, hops are locally-grown Brewer's Gold and Hallertau.
Unfortunately, as a fellow-Belgian, I have to concur with UncleBrazzie about Hommelbier: I've never been impressed with it, it simply does not stand out. Have even been at the famous Hommelhof mentioned in the article. It's located in a pretty village, far far away from home, in Flanders Fields, and that makes it special. But the #1 brewery of Watou shall remain St Bernardus.
This said, I'll see whether I can pick up a bottle and try the beer again with more attentive taste buds.