Don't think it's a version issue, I have the following 
HTML::Mason         : 1.48
HTML::Mason::ApacheHandler: 1.69
mod_perl2           : 2.000005

[download]
Tried using PerlResponseHandler, but the result is the same.

In reply to Re^2: Using Mason with Mod_Perl 2 and getting "did not send an HTTP header" error by Anonymous Monk
in thread Using Mason with Mod_Perl 2 and getting "did not send an HTTP header" error by beanryu

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