My alpha seems to be picky about doing floating point division by zero.  It
will only allow it under very specific circumstances:

* When the zero is explicitly 0.0
* When it contains only numbers and no variables.

xpath.c does division by zero for the infinity and NaN vars, and it causes
a FPE.  
Patch:

--- xpath.c.orig	Sat Apr  7 23:28:53 2001
+++ xpath.c	Sat Apr  7 23:29:14 2001
@@ -164,14 +164,11 @@
 
     if (initialized) return;
 
-    xmlXPathNAN = 0;
-    xmlXPathNAN /= 0;
+    xmlXPathNAN = 0/0.0;
 
-    xmlXPathPINF = 1;
-    xmlXPathPINF /= 0;
+    xmlXPathPINF = 1/0.0;
 
-    xmlXPathNINF = -1;
-    xmlXPathNINF /= 0;
+    xmlXPathNINF = -1/0.0;
 
     initialized = 1;
 }