Use /tmp for cache files since the user won't have
write permissions on ${DOCDIR}.

diff -Naurp docs-orig/viewdocs.py docs/viewdocs.py
--- docs-orig/viewdocs.py	2008-09-28 15:59:16.000000000 -0600
+++ docs/viewdocs.py	2009-01-18 00:16:27.000000000 -0600
@@ -16,11 +16,11 @@ if not basePath:
 
 
 # test for write access
-if os.access(basePath, os.W_OK):
+if os.access('/tmp', os.W_OK):
 
     # setup the args
     args = ['',
-        '--cache='+basePath,
+        '--cache=/tmp',
         os.path.join(basePath, 'wx.zip'),
         ]