I am sorry - that is a bug introduced in (probably) 1.5 . I have just fixed it. Thank you for reporting it.
I will try to upload the fixed unstable to http://pgfplots.sourceforge.net/ soon. Thus, even if it might still take some weeks until I submit a bugfix release to CTAN, you have the option to download that version and install it locally to fix the problem.
Best regards
Christian
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Hi Magnus,
I am sorry - that is a bug introduced in (probably) 1.5 . I have just fixed it. Thank you for reporting it.
I will try to upload the fixed unstable to http://pgfplots.sourceforge.net/ soon. Thus, even if it might still take some weeks until I submit a bugfix release to CTAN, you have the option to download that version and install it locally to fix the problem.
Best regards
Christian