> I noticed 3.08.3 is a bug fix release. Where can I find 
> information on 
> the bug that is solved in it?
> 

ocaml-3.08.3/Changes:

Objective Caml 3.08.3:
----------------------

New features:
- support for ocamlopt -pack under Mac OS X (PR#2634, PR#3320)
- ignore unknown warning options for forward and backward compatibility
- runtime: export caml_compare_unordered (PR#3479)
- camlp4: install argl.* files (PR#3439)
- ocamldoc: add -man-section option
- labltk: add the "solid" relief option (PR#3343)
- compiler: ocamlc -i now prints variance annotations

Bug fixes:
- typing: fix unsoundness in type declaration variance inference.
    Type parameters which are constrained must now have an explicit variant
    annotation, otherwise they are invariant. This is not backward
    compatible, so this might break code which either uses subtyping or
    uses the relaxed value restriction (i.e. was not typable before 3.07)
- typing: erroneous partial match warning for polymorphic variants (PR#3424)
- runtime: handle the case of an empty command line (PR#3409, PR#3444)
- stdlib: make Sys.executable_name an absolute path in native code (PR#3303)
- runtime: fix memory leak in finalise.c
- runtime: auto-trigger compaction even if gc is called manually (PR#3392)
- stdlib: fix segfault in Obj.dup on zero-sized values (PR#3406)
- camlp4: correct parsing of the $ identifier (PR#3310, PR#3469)
- windows (MS tools): use link /lib instead of lib (PR#3333)
- windows (MS tools): change default install destination
- autoconf: better checking of SSE2 instructions (PR#3329, PR#3330)
- graphics: make close_graph close the X display as well as the window
(PR#3312)
- num: fix big_int_of_string (empty string) (PR#3483)
- num: fix big bug on 64-bit architecture (PR#3299)
- str: better documentation of string_match and string_partial_match
(PR#3395)
- unix: fix file descriptor leak in Unix.accept (PR#3423)
- unix: miscellaneous clean-ups
- unix: fix documentation of Unix.tm (PR#3341)
- graphics: fix problem when allocating lots of images under Windows
(PR#3433)
- compiler: fix error message with -pack when .cmi is missing (PR#3028)
- cygwin: fix problem with compilation of camlheader (PR#3485)
- stdlib: Filename.basename doesn't return an empty string any more
(PR#3451)
- stdlib: better documentation of Open_excl flag (PR#3450)
- ocamlcp: accept -thread option (PR#3511)
- ocamldep: handle spaces in file names (PR#3370)
- compiler: remove spurious warning in pattern-matching on variants
(PR#3424)
- windows: better handling of InterpreterPath registry entry (PR#3334,
PR#3432)

Christoph Bauer