InfoPath Dev

I have a repeating table in me form. One of the items there is "itemNumber". It have to be 1, 2, 3, 4 and so on in each new repeating table. I mean on the first table it should be automatically created "1" in the "itemNumber". Then, when i create a new one table, it should be "2" in the "itemNumber". How can i do this? I saw that in one template but when i compared properties from template and mine i didn't find any differance. Help plz.

Can you attach a copy of your form under the options tab? I can give you hand. You'll need to use a preceding-sibling formula.

Oh, thx. I've solved this problem already. But now i have a new one. Maybe you can help me. I have two drop-down lists. I need them to depend on each other. I have for example 30 values in the second list and 5 in the first one. When i choose in the first list any value, there should be for example 20 from 30 values only and other shouldn't be displayed in the second drop-down list. And so on with all the 5 values in the first list. For each value in the first list there should be different and some same values in the second list.