RSS feeds lack standard pubDate field

RSS feeds generated by SPIP lack the standard pubDate data type. As a result, importing these feeds with any tool that follows the W3C standard results in posts marked with the date when they were imported instead of the date when they were originally published. This can be very annoying, especially when importing a years-old archive with hundreds of posts.

SPIP's RSS feeds do have dc:date fields but they are something different, and non-standard (see xml - what is the difference between pubDate and dc:date in feed's structure - Stack Overflow).