Undefined method errors in rails

Hi all,

I am currently developing a rails application. After a webserver reboot
I often get undefined method errors which are caused by wrong types.

I am using a Builder::XmlMarkup object but sometimes it is interpreted
as Fixnum resulting in those undefined method errors. But normally the
code just works.

Does someone have similar problems or is this only a problem/bug in some
rails specific classloading code? Could someone clarify how classloading
works in ruby? Some classes are autoloaded, others aren’t?

Rails is version 2.0.2, Ruby is 1.8.6

Daniel