Parameters in Persistent MDO query

Hi everybody,

I have a problem in my MII14 project

I created a Persisten MDO retriving data from a table.

After i create a MDO query for search a field in this MDO. I need use this query inside my transaction.

My filter Expression is like this:

[MEASUREMENTS_CENTER] = '[Param.1]', but when i try to test query i have this error:

java.lang.StringIndexOutOfBoundsException: String index out of range: -1

If i change Expression in [MEASUREMENTS_CENTER] = '[ObjectParam.1]' i don't have error but when i test query I don't see any data.

Any suggestion?

thanks in advance

PS: I want use MDO because i want reduce DB access in my transaction and encrease performance

Alessandro