PHP warnings in apache log file (Call-time pass-by-reference has been deprecated)

On drupal 5.5 with i18nsync.module 5.x-2.2 I have a lot of PHP warnings and the Apache log file grows rapidly:

[Sat Dec 08 08:43:43 2007] [error] [client xxx] PHP Warning: Call-time pass-by-reference has been deprecated - argument passed by value; If you would like to pass it by reference, modify the declaration of [runtime function name](). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. However, future versions may not support this any longer. in /local/websites/test01.urlfilterdb.com/sites/all/modules/i18n/experimental/i18nsync.module on line 142, referer: http://test01.urlfilterdb.com/en/admin/settings/i18n

[Sat Dec 08 08:43:53 2007] [error] [client xxx] PHP Warning: Call-time pass-by-reference has been deprecated - argument passed by value; If you would like to pass it by reference, modify the declaration of [runtime function name](). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. However, future versions may not support this any longer. in /local/websites/test01.urlfilterdb.com/sites/all/modules/i18n/experimental/i18nsync.module on line 142, referer: http://test01.urlfilterdb.com/en/admin/settings/locale/

[Sat Dec 08 08:44:04 2007] [error] [client xxx] PHP Warning: Call-time pass-by-reference has been deprecated - argument passed by value; If you would like to pass it by reference, modify the declaration of [runtime function name](). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. However, future versions may not support this any longer. in /local/websites/test01.urlfilterdb.com/sites/all/modules/i18n/experimental/i18nsync.module on line 142, referer: http://test01.urlfilterdb.com/en/admin/content

[Sat Dec 08 08:44:24 2007] [error] [client xxx] PHP Warning: Call-time pass-by-reference has been deprecated - argument passed by value; If you would like to pass it by reference, modify the declaration of [runtime function name](). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. However, future versions may not support this any longer. in /local/websites/test01.urlfilterdb.com/sites/all/modules/i18n/experimental/i18nsync.module on line 142, referer: http://test01.urlfilterdb.com/en/admin

[Sat Dec 08 07:45:01 2007] [error] [client xxx] PHP Warning: Call-time pass-by-reference has been deprecated - argument passed by value; If you would like to pass it by reference, modify the declaration of [runtime function name](). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. However, future versions may not support this any longer. in /local/websites/example.com/sites/all/modules/i18n/experimental/i18nsync.module on line 142