Mehl, who was vice-president of international advertising and communication at the German mobile giant, is joining in the new role of managing director of sales and communications. He will take overall responsibility for Wanadoo's £15m marketing budget.
Hawkins quit Freeserve just weeks before its £20m Wanadoo rebrand, to become the top marketer at wireless broadband start-up UK Broadband.
Mehl's hiring is one of three appointments, which will make up Wanadoo UK's management team.
Mark Overton, head of products and services at 3, is expected to join in the new role of managing director of strategy, products and services in the next few weeks. Deborah Sherry, Wanadoo portal channels director, is being promoted to managing director of portal revenues.
All three will report to chief executive Eric Abensur. Wanadoo refused to confirm Overton's appointment.
Wanadoo insists that marketing, communications and services director Peter Turner will stay with the firm and report to Mehl.
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