My work on [loading Lisp from JAR files has been committed to trunk][1].
With this modification, you may now package up the results of COMPILE-FILE (the packed FASLs ending in '.abcl') in a JAR file for loading with ABCL.
For example,
(load "jar:file:///PATH/TO/the.jar!/foo")
would load the forms contained in "foo.abcl" packaged in the "/PATH/TO/the.jar" (relative paths for the 'file:' URI work as well).
[1]: http://trac.common-lisp.net/armedbear/changeset/12141
Test code has been included, but currently only works under UNIX due to needing to pack the JAR file for testing via an external script.
Further things that should be eventually be addressed (by me, I presume):
1) The Load.load() function could use some re-factoring. This has proved to be rather difficult (or maybe I am just not thinking correctly in Java anymore), as my refactorings keep turning out longer and *more* convoluted than what is present. I wanted to get the functionality out there with some tests as it seems the community (i.e. Alan) would like to use this sooner rather than later.
2) Load from JARs not on local filesystem ("jar:http://here.we.go/application.jar").
3) Test what the *load-truename* variable gets bound to a little more rigorously