IPsec is widely used to provide secure access to corporate private networks. IPsec is specified by TISPAN and 3GPP for both access, core and interconnect applications. However, IPsec and the current range of corporate network edge Network Address and Port Translators (NAPTs) are not compatible with the Next Gen services provided by VoIP architectures. This paper examines the compatibility issues that exist between the Next Gen services provided by VOIP Architectures and the current IPSec Protocol.