Parameters (Escape Codes) for a chat room

what parameters (escape code) can be used for a mutli-word parameter, while
only using a single escape code???

i am  developing a open source SMS chat room,
i have open question, i would like to use ONE  Parameters (Escape Codes) to
accept the chat room name and ONE to accept the CHAT content for example the
user would type the following " GENERAL hello all my name is Patrick"
the keyword would be "GENERAL" and the chat content would be "hello all my
name is Patrick"
i would expect the setup to look like this
get-url = "http://digipoint1-sms.net/sms/chat.asp?topic=%s&content=%s"

however  i get a "could not fetch content error " if the "content"  has more
than one WORD.

what parameters (escape code) can be used for a mutli-word expression, while
only using a single escape code?