That's actually quite easy to do in graphviz, simply put some quotes around the node names. Or you may define first your node using a simple identifier and a label
attribute.
Both techniques demonstrated here:
digraph g {
"java.lang.object" -> "my.class";
"my.class" -> "special < chars >";
n1 [label="more.strange<node>names"];
"special < chars >" -> n1;
}