bean:define tag

Question: How do I handle nulls with the bean:define tag?  I have a bean
with a collection attribute.  I use the define tag to put the collection
into the page scope so I can iterate over it.  But if the collection is
null I get a null pointer exception (of course).

Is there a way to use the existing taglibs that can deal with this
situation or do I have to extend the library (or resort to putting code
in my jsp)?