I confirm this is working.
In order to keep the library compatible with Moteino (AVR) and ESP8266 I did the following modification to the ISR handling function (according the the RFM69 Library version):
#if defined (ESP8266)
ICACHE_RAM_ATTR void RFM69::isr0() { <what ever is specified in the current version> }
#else
void RFM69::isr0() { <what ever is specified in the current version> }
#endif
Robert