"Use of uninitialized value" running "git svn clone" when having svn tag branches

I'm trying to convert a project (hosted in googlecode.com) from svn to
git, using the "git svn clone" command, and I'm getting an "Use of
uninitialized value" error. Here's the truncated output:

$ git svn clone https://test-libraries-for-java.googlecode.com/svn
--no-metadata -A ~/tmp/authors.txt -t tags -b branches -T trunk
test-libraries-for-java
 r1 = c3adafa93a420f19b1bcfb6765fe0eb90aaa751c (refs/remotes/trunk)
       A       .classpath
       A       .project
       A       COPYING
       A       build.properties
       A       build.xml
W: +empty_dir: trunk/src
[...]
r10 = 8d5d7fdebdb7f822388fd3e4f4061abbfd1fb0cf (refs/remotes/trunk)
       M       test/com/google/common/testing/junit3/JUnitAssertsTest.java
r11 = 4c8a77660bf353ed55c9d583b39e263203c685a4 (refs/remotes/trunk)
Found possible branch point:
https://test-libraries-for-java.googlecode.com/svn/trunk =>
https://test-libraries-for-java.googlecode.com/svn/tags/release-1.0,
11
Use of uninitialized value $u in substitution (s///) at
/usr/lib/git-core/git-svn line 1731.
Use of uninitialized value $u in concatenation (.) or string at
/usr/lib/git-core/git-svn line 1731.
refs/remotes/trunk:
'https://test-libraries-for-java.googlecode.com/svn' not found in ''

For completeness, here's the authors.txt file I'm using:

$ cat ~/tmp/authors.txt
zorzella = Luiz-Otavio 'Z' Zorzella [off-list ref]
(no author) = Luiz-Otavio 'Z' Zorzella [off-list ref]

**************

The same command works fine if I don't use the "-t tags" part, but
then it does not create the tag branches in my converted git.

Thanks in advance,

Z