Weird behaviour of a Web Service

Hello everyone,

I’m currently writing a Rails application which should expose some web
methods, which need to be called by a windows mobile application.
I’ve been able to successfully call some webmethods from the mobile
application, but only the methods returning simple types as strings,
numbers, arrays etc.

Now I need to expose a method which receives an ActiveRecord object.
In this case, I’ve witnessed a strange behaviour.
If I write my method this way:

def get_role(role_id)
a = Role.find(role_id)
return a

I get a “Cannot map Role to SOAP/OM” exception from the mobile
application. Googling this error has lead me to this page:

so I rewrote the method as:

def get_role(role_id)
a = Role.find(role_id)
return => “#{a.description}”, …[all the
attributes here])

but in this case, the mobile application gives me a “FormatException”
I cannot understand why, even if I’m returning a Role object in both
cases, I get two different error messages!
Where or what am I doing wrong?

Thanks in advance!