SYSTEM WARNING after upgrade

[vchalana]

I have upgraded Mantis 0.19.2 to 1.0.8.

After upgrading database and all files, when I logon to Mantis, I get this warning on many pages:

SYSTEM WARNING: call_user_func_array() [function.call-user-func-array]: First argumented is expected to be a valid callback, 'custom_function_default_get_columns_to_view' was given

I am completely lost on this. Any help from anyone would be highly appreciated!

Thanks in advance.

[sdguero]

Any ideas on how to fix?