Summary of my perl5 (revision 5 version 8 subversion 6) configuration:
  Platform:
    osname=MSWin32, osvers=4.0, archname=MSWin32-x86-multi-thread
    uname=''
    config_args='undef'
    hint=recommended, useposix=true, d_sigaction=undef
    usethreads=define use5005threads=undef useithreads=define usemulti
+plicity=define
    useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cl', ccflags ='-nologo -Gf -W3 -MD -Zi -DNDEBUG -O1 -DWIN32 -D
+_CONSOLE -DNO_STRICT -DHAVE_DES_FCRYPT  -DNO_HASH_SEED -DPERL_IMPLICI
+T_CONTEXT -DPERL_IMPLICIT_SYS -DUSE_PERLIO -DPERL_MSVCRT_READFIX',
    optimize='-MD -Zi -DNDEBUG -O1',
    cppflags='-DWIN32'
    ccversion='', gccversion='', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=10
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='__int64
+', lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='link', ldflags ='-nologo -nodefaultlib -debug -opt:ref,icf  -l
+ibpath:"C:\Perl\lib\CORE"  -machine:x86'
    libpth=\lib
    libs=  oldnames.lib kernel32.lib user32.lib gdi32.lib winspool.lib
+  comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib  netap
+i32.lib uuid.lib ws2_32.lib mpr.lib winmm.lib  version.lib odbc32.lib
+ odbccp32.lib msvcrt.lib
    perllibs=  oldnames.lib kernel32.lib user32.lib gdi32.lib winspool
+.lib  comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib  n
+etapi32.lib uuid.lib ws2_32.lib mpr.lib winmm.lib  version.lib odbc32
+.lib odbccp32.lib msvcrt.lib
    libc=msvcrt.lib, so=dll, useshrplib=yes, libperl=perl58.lib
    gnulibc_version='undef'
  Dynamic Linking:
    dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags='-dll -nologo -nodefaultlib -debug -opt:
+ref,icf  -libpath:"C:\Perl\lib\CORE"  -machine:x86'


Characteristics of this binary (from libperl): 
  Compile-time options: MULTIPLICITY USE_ITHREADS USE_LARGE_FILES PERL
+_IMPLICIT_CONTEXT PERL_IMPLICIT_SYS
  Locally applied patches:
    ActivePerl Build 811
    21540 Fix backward-compatibility issues in if.pm
    23565 Wrong MANIFEST.SKIP
  Built under MSWin32
  Compiled at Dec 13 2004 09:52:01
  @INC:
    C:/Perl/lib
    C:/Perl/site/lib
[download]

R is version 2.1.1 :)

P.S Do you think it might help to try an older Perl version if something sig. changed in 5.8 to do with this? The pm hasn't been updated for 12 months so maybe its deprecated?