Sorry to say, but your custom rule works as implemented: only if value "
b" is selected, the list of selected values is equal to ... "
b", while if value "
b" AND "
c" are selected, then the list of selected values is NOT equal to ... euh ... "
To get your rule to work like you want it to work, then you should use these Rules Conditions (in the specified order):
- Entity has field, for your "checkboxes" field.
- List contains item, whereas:
- the list is also about that same "checkboxes" field (since your field allows multiple values, it is also considered as a list).
- the item you want to check for (if it is contained in the list) is "
With those 2 Rules Conditions, your Rules Actions should be perform (1) if only value "
b" was selected, but (2) also if value "
b" and value "
c" were both selected.
For an example Rule (in rules export format) in which you can see this at work, refer to the answer to "How to check for product taxonomy term in Rules actions (Ubercart)". In that case it's about a list of taxonomy terms, but the idea is the same.
PS: even though CCK is rather D6-ish, the same kind of mistake can happen in D7 (which is what my answer is about).