Adding a new node to the executor

Hey guys,
I am taking my chances of posting a devel doubt on this list (couldn't find
any other relevant list). I think I have spent too much time on
this and need a fresh pair of eyes to look in it..

So this is my situation:
1. I have added a new field to RangeTblEntry (bool tablesample).

2. I have created a new executor node (this is to do system sampling
[Ref: Query sampling thread]). In short, this new node goes over a table
block by block, skipping some blocks as required.

3. Have made the appropriate changes to the parser+planner so that the
information about a tablesample is passed from the parser to the executor.

But the RangeTblEntry received by my executor node does
not have the tablesample set, inspite of the fact that I do set it in
parse_relation.c:addRangeTableEntry().

I have made the appropriate changes to copyfuncs.c, but still in vain..
Any help would be highly appreciated. I can send a diff if someone is
interested.

Thanks
Varun