I've implemented a custom document handler for my iOS application (based on this question & answer: How do I associate file types with an iPhone application?) and in general it's working fine. However, if I try to open a mail attachment of my document type that's greater than 1.5MB, my document icon does not display (a generic download arrow does) and Mail will not open the attachment, instead responding with the message "Mail cannot open this attachment".
I can 'trick' Mail into loading the attachment by beginning to forward the message with attachments, waiting for the attachment to download, and then returning to the original message. Once it's been actually downloaded, it opens fine with my app.
My question is, how can I get Mail to recognize that my document is supported, so that it will allow downloading the attachment (like it does for large PDFs, for example)?
