Paypal express checkout Gateway.setup_purchase = ArgumentError: wrong number of arguments (1 for 0)

[johnnybutler7]

Hi,

Im using rails 3.1.0 and Activemerchant 1.18.1 and i keep getting the
above error when trying to setup a purchase. I cant figure out why.
Anybody got any ideas? Ive followed the railscasts here
http://railscasts.com/episodes/146-paypal-express-checkout and cant
see why i should be receiving this error. Any ideas?


EXPRESS_GATEWAY.setup_purchase(100, {:return_url =>
"www.bbc.co.uk", :cancel_return_url => "www.bbc.co.uk"})
ArgumentError: wrong number of arguments (1 for 0)
from /Users/jxxxxxxxxxr/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlbase.rb:135:in `to_xs'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlbase.rb:135:in `_escape'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlbase.rb:140:in `_escape_quote'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlmarkup.rb:320:in `_attr_value'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlmarkup.rb:311:in `_insert_attributes'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlmarkup.rb:310:in `each'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlmarkup.rb:310:in `_insert_attributes'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlmarkup.rb:293:in `_start_tag'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlbase.rb:60:in `method_missing'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
builder-3.0.0/lib/builder/xmlbase.rb:34:in `tag!'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
activemerchant-1.18.1/lib/active_merchant/billing/gateways/
paypal_express.rb:97:in `build_setup_request'
from /Users/xxxxxxxx/.rvm/gems/ree-1.8.7-2010.02@mystaffdeals/gems/
activemerchant-1.18.1/lib/active_merchant/billing/gateways/
paypal_express.rb:25:in `setup_purchase'