Here is what the log says:
2007-11-04T22:43:39 <6> [ppm:81] ppm install XML::LibXML::Common
2007-11-04T22:43:39 <7> [Client.pm:429] http://ppm4.activestate.com/MS
+Win32-x86/5.8/822/package.xml is still fresh
2007-11-04T22:43:39 <7> [Client.pm:429] http://theoryx5.uwinnipeg.ca/p
+pms/package.xml is still fresh
2007-11-04T22:43:39 <7> [Client.pm:429] http://trouchelle.com/ppm/pack
+age.xml is still fresh
2007-11-04T22:43:40 <7> [Client.pm:836] Want XML::LibXML::Common >= 0
2007-11-04T22:43:40 <7> [Client.pm:711] Feature XML::LibXML::Common no
+t found in site
2007-11-04T22:43:40 <7> [Client.pm:711] Feature XML::LibXML::Common no
+t found in perl
2007-11-04T22:43:40 <7> [Client.pm:719] Module XML::LibXML::Common not
+ found in @INC
2007-11-04T22:43:40 <7> [Client.pm:711] Feature XML::LibXML::Common no
+t found in site
2007-11-04T22:43:40 <7> [Client.pm:711] Feature XML::LibXML::Common no
+t found in perl
2007-11-04T22:43:40 <7> [Client.pm:719] Module XML::LibXML::Common not
+ found in @INC
2007-11-04T22:43:40 <5> [ppm:1114] Installing into site
2007-11-04T22:43:43 <6> [Web.pm:63] GET http://theoryx5.uwinnipeg.ca/p
+pms/x86/XML-LibXML-Common.tar.gz ==> 200 OK (40159 bytes in 2.92 sec
+- 13 KB/s)
2007-11-04T22:52:31 <3> [ppm:85] ppm install: Could not open 'C:\data\
+tmp\ppm-P6gd5t/XML-LibXML-Common-0.13/blib/lib/XML/LibXML/Common.pm':
+ No such file or directory at C:/data/Perl/lib/ActiveState/ModInfo.pm
+ line 144. ...propagated at C:\data\Perl\bin/ppm line 998, <STDIN> li
+ne 1.
It does not seem to be a matter of rights not set properly (see update 1 above), since a script I wrote can do the extraction. Anyhow, I'm running now as "Admin" with full rights, but still no luck.
CountZero
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James