NoMethodError in User sessionsController#create

Having a frustrating go at authenticating a user, pretty sure it must
have something to do with gem version conflicts, but I can't seem to
find a solution that works.

No matter what username & password that is entered into the login form I
get the same error screen:

NoMethodError in User sessionsController#create
undefined method `protected_password' for #<UserSession:
{:login=>"rtgh", :password=>"<protected>"}>

Trace:
.../vendor/plugins/authlogic_ldap/lib/authlogic_ldap/session.rb:251:in
`send'
.../vendor/plugins/authlogic_ldap/lib/authlogic_ldap/session.rb:251:in
`validate_by_ldap'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:178:in
`send'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:178:in
`evaluate_method'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:166:in
`call'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:93:in
`run'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in
`each'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in
`send'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:92:in
`run'
.../vendor/rails/activesupport/lib/active_support/callbacks.rb:276:in
`run_callbacks'
.../vendor/plugins/authlogic/lib/authlogic/session/callbacks.rb:83:in
`validate'
.../vendor/plugins/authlogic/lib/authlogic/session/validation.rb:64:in
`valid?'
.../vendor/plugins/authlogic/lib/authlogic/session/existence.rb:65:in
`save'
.../app/controllers/user_sessions_controller.rb:13:in `create'
.../app/controllers/user_sessions_controller.rb:12:in `create'

I've installed the ruby version of Netbeans, and the only output from
'gem list' is:
*** LOCAL GEMS ***

net-ldap (0.1.1)
rack (1.0.1)
rake (0.8.7)
sqlite3-ruby (1.3.1 x86-mingw32)

Doesn't make sense to me, my buddy has the exact same gems on his
machine, yet he is able to start up the server, run code and log in
without problems.

Suggestions would be wonderful

.....