Wagn 1.8.2 problems with apache and passenger?

We have been using wagn since 0.13 and have recently upgraded it to 1.8.2. Everything works perfectly when used on webrick server and there are no errors whatsoever. However, while running the application via apache/passenger, we are getting runtime errors on certain cards with error  "No card name for class" 

Here is the stack trace:-

app/models/cardtype.rb:54:in `name_for'
app/models/card.rb:369:in `typename'
lib/wagn/model/pattern.rb:86:in `opt_vals'
lib/wagn/model/pattern.rb:52:in `set_name'
lib/wagn/model/pattern.rb:28:in `map'
lib/wagn/model/pattern.rb:28:in `set_names'
lib/wagn/model/pattern.rb:29:in `real_set_names'
lib/wagn/model/settings.rb:9:in `rule_card'
lib/wagn/model/templating.rb:14:in `get_template'
lib/wagn/model/templating.rb:10:in `template'
app/models/card.rb:86:in `get_typecode'
app/models/card.rb:63:in `initialize'
app/models/card.rb:50:in `new'
app/models/card.rb:50:in `new'
app/controllers/application_controller.rb:103:in `render_errors'
app/controllers/application_controller.rb:172:in `__bind_1351582053_511193'

What can be the cause of this error and what is the solution?