Suggestions for monitoring tools?

I've been asked by one of our clients to take over monitoring their Oracle database. I'm still trying to find out exactly what they want us to do; to me that means running something like Spotlight from Quest. However, there's probably no budget to buy tools, and we are exclusively Linux and Mac so can't run anything that requires Windows (not without some pain, anyway). So I'm looking for suggestions for tools that run on some form of Unix, preferably a Mac. Cheap or free is secondary; I might be able to get them to buy me something but unless it will run on my desktop or one of our servers it won't do me much good. Oh, their database is running on a Solaris server.

Any suggestions?

thanks,

janine

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