guid: (len.36)*
sender: (len.50)*
recipient: (len.50)*
priority 1 (highest) 2 (high) 3 (normal) 4 (low) 5 (lowest)
subject: (len.50)*
msg: (len. 1024)
receipt: (len.1)
lat: (len.12)
lon: (len.12)
format json