Valid characters in “From:” display name for emails

[lineay]

I am using PEAR Mail to send emails, and I found that if the "From:" field is something like \[code\]From: Drago? <[email protected]>\[/code\], PEAR returns an error:\[code\]Validation failed for: Drago? <[email protected]>\[/code\]But, if I remove the \[code\]?\[/code\], PEAR returns true and sends email.I tried to search on Google and StackOverflow for valid characters, but seems I have no luck here.Does anyone know what are the valid characters for the display name in From field?Also, is there any way to "encode" these chars to be allowed on this field? I use PHP.Thank you!
Nuno