Thanks, Joe. I had tried several values for LD_ASSUME_KERNEL and also tried yours to no avail. The sad part is that this error:
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Unable to load native library: /tmp/OraInstall2004-02-09_04-51-53PM/jre/lib/i386/libjava.so: symbol __libc_wait, version GLIBC_2.0 not defined in file libc.so.6 with link time reference
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...(I believe) is just from the JRE, and since the Oracle Installer appears to be using its own (in the /tmp directory), there appears to be no way to fix it. I diddled with the runInstaller script to make it point to my version of java, but it does the same thing.

Also tried to install 10g (!!), which at least said "no" cleanly:
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$ runInstaller
Starting Oracle Universal Installer...

Checking installer requirements...

Checking operating system version: must be redhat-2.1, UnitedLinux-1.0 or redhat-3
Failed <<<<

Exiting Oracle Universal Installer, log for this session can be found at /tmp/OraInstall2004-02-09_04-37-05PM/installActions2004-02-09_04-37-05PM.log
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