Since JavaOne slides were posted, I’ve been trying go through what I’ve missed during the conference. Dolphin (Java 7 or whatever it will be called) should attack the “Jar-hell” problem (I feel your pain too) with JSR 277. In the mean time you’ll get things like this in Mustang (Java 6) in 2006:
% javac -cp .:./lib/jsfcl.jar \\
% javac -cp '.:./lib/\*.jar' Application.java
Not sure it helps with complex situation (may actually burden in some cases), but I’m sure many will enjoy this. Much more to read in Mark Reinhold‘s TS-7264 presentation.