Work to migrate Europe to the net's new addressing system must speed up, says the European Commission.
The call to action is contained in a plan sent to the European Parliament urging governments and top websites in the region to head the migration.
It warns that internet-based innovation could be derailed as the current pool of addresses is used up.
The plan sets a target of 25% of net users in the EU to be using the new system by 2010.
"This is very much a case of a stitch in time saves nine," said Viviane Reding, EU Commissioner for the information society, in a statement unveiling the plan.
Ms Reding said futuristic technologies already being adopted, such as smart tags, intelligent street lighting and heating systems, were already projected to boost demand for IP addresses 1,000-fold - perhaps beyond the current system's ability to cope.
Europe could face a "crisis" when the older system ran out of addresses, she warned.
Currently, Version 4 of the Internet Protocol (IPv4) is used to ensure that data travelling across the net reaches the right destination.
The IPv4 scheme makes available about 4.3 billion addresses - a total predicted to run out in 2011.
By contrast, Version 6 of this scheme (IPv6) provides, in effect, an unlimited number of addresses.
The "huge address space provides a platform for innovation in IP-based services and applications," said the commission in its plan.
The steps outlined in the plan are intended to build on the work already done to get Europe using IPv6.
For instance, Geant, the high-speed data network linking many European research centres, is already 100% IPv6 compatible, said the plan.
Governments should migrate their core networks to IPv6 and add a requirement for it to public procurement contracts, said the plan. It also wants the top 100 websites in Europe to be reachable by IPv6 by the 2010 deadline.