Por ahora, esto no es posible.
Aquí está la documentación
sobre lo que se puede usar en el FROM
cláusula:
table_references:
table_reference [, table_reference] ...
table_reference:
table_factor
| join_table
table_factor:
tbl_name [[AS] alias] [index_hint)]
| table_subquery [AS] alias
| ( table_references )
| { OJ table_reference LEFT OUTER JOIN table_reference
ON conditional_expr }
join_table:
table_reference [INNER | CROSS] JOIN table_factor [join_condition]
| table_reference STRAIGHT_JOIN table_factor
| table_reference STRAIGHT_JOIN table_factor ON conditional_expr
| table_reference {LEFT|RIGHT} [OUTER] JOIN table_reference join_condition
| table_reference NATURAL [{LEFT|RIGHT} [OUTER]] JOIN table_factor
join_condition:
ON conditional_expr
| USING (column_list)
index_hint:
USE {INDEX|KEY} [FOR JOIN] (index_list)
| IGNORE {INDEX|KEY} [FOR JOIN] (index_list)
| FORCE {INDEX|KEY} [FOR JOIN] (index_list)
index_list:
index_name [, index_name] ...
Como puede ver, los procedimientos almacenados no están en esta lista.