BigInteger and BigDecimal datatypes are converted into string in MongoDB translator

Description of problem:

BigInteger and BigDecimal datatypes are converted into string in MongoDB translator (MongoDBExecutionFactory.java). User can't use these datatypes in the WHERE clause.

For example
The query:

SELECT IntKey FROM SmallA where BIGINTEGERVALUE > 1

returns no results because BIGINTEGERVALUE > 1 is converted into

{ "BIGINTEGERVALUE" : { "$gt" : "1"}}

but is should be

{ "BIGINTEGERVALUE" :

}