The ChangeLog for unknownR is the SVN commit log itself :
    $ svn log svn://svn.r-forge.r-project.org/svnroot/unknownR

This NEWS file summarises the main changes.


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        **   CHANGES IN UNKNOWNR VERSION 0.4   **
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o installed.packages() now called with lib.loc=.Library as requested
  by Prof Ripley for efficiency when all packages are installed.

o onAttach now uses packageStartupMessage.



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        **                                     **
        **   CHANGES IN UNKNOWNR VERSION 0.3   **
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BUG FIXES

    o   Variables assigned in your Rprofile.site are installed
        by R in base; these no longer cause unk() to fail. Thanks
        to Richard Cotton for the bug report (#1403) and fix.
        
        

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        **                                     **
        **   CHANGES IN UNKNOWNR VERSION 0.2   **
        **                                     **
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NEW FEATURES

    o   unk gains delay and redDelay arguments: the number of
        seconds each function is displayed (3) and then turned
        red (2).
        
    o   unk gains pkgs argument, by default c("base","utils").
        Any set of packages can be passed here, as suggested
        by Jean-Robert Avettand-Fenoel (FR#1320). Accordingly,
        ~/.knowns.Rdata now saves the package of each function
        for cases where the same function name is in several
        packages.
        
    o   The .Rd manual page is retrieved and functions from
        internal pages (such as ns-internal and base-internal)
        are filtered, reducing 878 to 809 (as of R 2.12.1).
        
    o   learn() now saves a learn()-ed status to .knowns.Rdata
        so you can come back to learn() later and continue
        where you left off. Thanks to Sean O'Riordain for the
        suggestion.
        
    o   unk() no longer returns 'tolearn'. learn() reads this
        from .knowns.Rdata directly. Thanks to Sean O'Riordain
        for the suggestion.
        
    o   The top 30 (by default) packages from Crantastic are
        included in the list (FR#1042), as are all base and
        recommended packages.



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        **                                        **
        **   VERSION 0.1 RELEASED CRAN MAR 2011   **
        **                                        **
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