Cannot define multiple predefined variables

I try to define in the predef variable a list as:
dojo,dijit

and when looking at the debug execution I see:

[DEBUG] Project/global setting name retrieved from global parameter: maxerr with value null
[DEBUG] Project/global setting name retrieved from global parameter: predef with value dojo
[DEBUG] Adding JSLint option from project/global settings: predef[The names of predefined global variables.] with value: dojo
[DEBUG] Adding Options Specified As Rule Parameters

So it seems that the system is not taking into account multiple values comma separated. This is valid if I define the setting at the global level or at the project level.