How many analog devices can you attach to a single PAP2T phone port in parallel?

I'm hoping to rewire the house moving the street connection to a seperate jack, and then plugging the PAP2T phone line into one of the three house jacks. (all in prep for Fusion) Does anyone know if this will work?

I have only 2 phones and the house alarm that I want to run over the single voIP line. The house alarm isn't monitored, just dials my cell on trigger events.