Ampersand encoding bug?

[wilmTap]

On one of my many happy SPARQLing expeditions I had cause to send out the following:

SELECT DISTINCT ?s ?x ?y WHERE { ?s rdfs:subClassOf ?x ; rdfs:subClassOf ?y . FILTER ( isIRI(?y) && (?y != owl:Class)) } LIMIT 10

To http://www.knoodl.com/ui/groups/ramlet/vocab/ramletCore/sparql Knoodl was not pleased and threw a 400 with "Encountered EOF at line 13, column 19" DBPedia was similarly disposed.

I tried the same query on knoodl and dbpedia's own SPARQL's forms, and they worked.

Since it's the only thing different with other queries I've run on Glint that do work && because a single "&" causes the same issue, I'm frowning with intent at the ampersand.