[rules-users] MVEL parsing / keyword conflict

Hi all, I've stumbled on some mvel integration issues in 5.0.1. I'm using drools to do, among others, spatial reasoning. At insertion time I maintain a specialized index, which can be queried later using [collect] from. This works fine in general. However, as soon as I use the mvel 2 projections a.k.a. 'in' keyword, hell breaks loose. 'in' is described here: http://mvel.codehaus.org/MVEL+2.0+Projections+and+Folds But I only seem to get syntax errors. If it is possible, to somehow escape keywords or explicitly pipe through the mvel part, please let me know! Needless to say, this feature would be great to have since my object model is mainly fixed and 'is' allows me to compensate that. Worse, I'd need to assert objects I don't want to assert to work around. I tried parenthesizing, only to discover that ... from valid_stmt is fine, but ... from (valid_stmt) won't work either. Error 101, reason unknown, but it doesn't even make it through the parser. I'd really appreciate to be given an idea why what I did went wrong. Googling around didn't get me too far. Cheers, Simon