Sorry if this is duplicate,I would think it would be but couldn\'t find anything.
I have a flex application that I am posting data back to a php/mysql server via IE.
It depends on a server configuration. If you're working with PHP under Linux or similar, you can control it using .htaccess configuration file, like so:
#set max post size
php_value post_max_size 20M
And, yes, I can personally attest to the fact that this works :)
If you're using IIS, I don't have any idea how you'd set this particular value.