Wilkosz: The Polish 2

Wilkosz 2 is very common in Poland, but banned in most other countries, perhaps because it is "too good". It is a good alternative to Multi 2 and is defined as:

2: Weak, 5 - 5, at least one major

Response to 2

Responses
Pass Own or suspects partner has them
2 Pass or bid 2
2 Pass or bid 3/
2NT Asks suits See below
3 To play
3 Invitational, at least 3 - 3 in majors
3NT To play

The relay 2NT

Opener now shows his suits in the following way:

2 - 2NT - ?
3 + / (3 asks the major)
3 +
3 +
3 +

Opponents Double

System on, Pass asks partner to pass if he has Diamonds, Redouble asks partner to pass even if he doesn't have Diamonds.

Opponents overcall with 2/

System on, double is pass or correct.