Java Database Connectivity (JDBC)

Hi All,
I appreciate this is a problem that has been posted a number of times so apologise for posting it again. I've read through a number of other posts on the topic and I'm about to start checking that our connections / statements are being closed in finally blocks but just have a couple of extra questions.

1) If ResultSets aren't closed, does it have the same implications as not closing a connection or statement? or will it just fall out of scope and get collected? (bad practices aside...)

2) We only have problems with connection leaks when the machine is under high load. I've verified this on a couple of different machines to make sure its not just a problem with the target machine. Does this ring a bell with anyone? (we're using SJSAS 9.0 and Oracle 10g with the ojdbc14.jar)

3) I read somewhere that there can be problems with growing the pool size quickly sometimes while the machine is getting a lot of grief (specifically when using SJSAS with Oracle), so tried setting both a minimum and maximum pool size of 50. Is this a point anyone else has come across? (tried it and it hasn't done a lot to alleviate the problem).

I have stack traces of three progressively worsening error's I can post if required.

Any pointers people can provide would be greatly appreciated :D
Cheers
Dave