This solved part of the problem. Thank you. As you will understand, this was not the real issue. The problem-script is a rather large one (140kB).

When the script packed with perlapp is started, the output is:

$ ./test
The following parameter was passed in the call to DateTime::Format::Bu
+ilder::Parser::create_single_parser but was not listed in the validat
+ion options: params
 at /</home/momo/test>DateTime/Format/Builder/Parser.pm line 311
    DateTime::Format::Builder::Parser::create_single_parser(undef, 'pa
+rams', 'ARRAY(0xa7b1440)', 'length', 'ARRAY(0xa7b3bf0)', 'postprocess
+', 'CODE(0xa7c3100)', 'regex', 'Regexp=SCALAR(0xa7b3e20)', ...) calle
+d at /</home/momo/test>DateTime/Format/Builder/Parser.pm line 501
    DateTime::Format::Builder::Parser::sort_parsers('DateTime::Format:
+:Builder::Parser', 'HASH(0xa4f4650)', 'ARRAY(0xa4f3c10)') called at /
+</home/momo/test>DateTime/Format/Builder/Parser.pm line 397
    DateTime::Format::Builder::Parser::create_multiple_parsers('DateTi
+me::Format::Builder::Parser', 'HASH(0xa4f4650)', 'HASH(0xa7b3e40)', '
+HASH(0xa7b4450)', 'HASH(0xa7b9368)', 'HASH(0xa20b008)', 'HASH(0xa20b1
+c8)', 'HASH(0xa7d0870)', 'HASH(0xa7d0950)', ...) called at /</home/mo
+mo/test>DateTime/Format/Builder/Parser.pm line 600
    DateTime::Format::Builder::Parser::create_parser('DateTime::Format
+::Builder::Parser', 'ARRAY(0xa635f30)', 'ARRAY(0xa7b3a60)', 'HASH(0xa
+7b3e40)', 'HASH(0xa7b4450)', 'HASH(0xa7b9368)', 'HASH(0xa20b008)', 'H
+ASH(0xa20b1c8)', 'HASH(0xa7d0870)', ...) called at /</home/momo/test>
+DateTime/Format/Builder.pm line 156
    DateTime::Format::Builder::create_parser('DateTime::Format::Builde
+r', 'ARRAY(0xa80fab8)') called at /</home/momo/test>DateTime/Format/B
+uilder.pm line 174
    DateTime::Format::Builder::create_end_parser('DateTime::Format::Bu
+ilder', 'ARRAY(0xa80fab8)') called at /</home/momo/test>DateTime/Form
+at/Builder.pm line 104
    DateTime::Format::Builder::create_class(undef, 'parsers', 'HASH(0x
+a51d450)') called at /</home/momo/test>DateTime/Format/Flexible.pm li
+ne 238
    eval '' called at perlapp line 810
    PerlApp::safe_eval() called at perlapp line 900
    PerlApp::my_require('DateTime/Format/Flexible.pm') called at test.
+pl line 105
    main::BEGIN() called at /</home/momo/test>DateTime/Format/Flexible
+.pm line 0
    eval {...} called at /</home/momo/test>DateTime/Format/Flexible.pm
+ line 0
BEGIN failed--compilation aborted at test.pl line 105.

Line 105: use DateTime::Format::Flexible;
[download]

Any suggestions on how to fix it?