once more ERROR: Unable to verify $_POST vars

Hi,

long story short. I too am faced with the Unable to verify $_POST vars problem after having used s2member for over a year without problems.

yes, I ran the server check script
yes, I verifed the shortcode
yes, I triple checked the paypal credentials
yes, I checked the log files

Upon purchase our customers are presented with the Unable to verify $_POST vars nag-screen.
The Paypal transaction IS successful and the IPN logs show correct handling.
Our customers DO NOT get a verification mail and the membership IS NOT set up in wordpress

after payment customers are returned to a URL like this one (WHICH Fails with the nag-screen) :
http://dutchmailer.com/?s2member_paypal_return=1&s2member_paypal_return_tra=fnIyOjIzR2ZyalJJdGwzdmZJODV4QUw1MExKaUE4RHVsRms0OjhlYzIwN2FlMWU3Y2I2ZDQwNzZhOWZmNWIyZjZmMTkzfINmyWpy4lNwHNIxz4OZ8emYM5LxmUPbkGSvtcLZez92AuF-LIKEAZZ_9BCmLQ8GXdXlBJ96RAn3dLQw8EbbYG2K_-DNHQGe392F_A1qacSzrc0kOyElK9J6DV1u0RyjU7RIF299M40htv9cMKIksY2vyPhCA_E3SPZXbznOUo-mSdWtDLQ2cnX4m7ibJunxQz-bVJc2T1DW4UzpyraQpuLFISb_e1WCqdgKP690bsSvd5oHXlPaJ5_q-hV8oNnvtydi19bgT9_VCH0YiqR58QONavLqE0FfhyXXZ_Xzq1o_YuE5tBtFoEQF4k7tl2QcLhdM3FE1XU15r-ml9F8myLExUad8Kb9j5FDoqfaKsM_8o7u1a2KakxiN9623oIMY_Q&tx=2LA52206S3386632X&st=Completed&amt=0.07&cc=EUR&cm=dutchmailer%2ecom&item_number=&sig=hMxvIJAJ6dK8wcQPOfpyc9Lnq7nP77Ib%2fOObFC8wB4WaK7Bvb3iDdSGWt%2f6BwqJM8lPLl0jrHPiUfFvMep6Xv343glRWdREqJ25m%2b5h1CStF6sObXFnCniHcuZcivg8bpq%2fFGmHf8YIfetMH9YYDWkvpeTJc%2fTAroRCL11tSUn0%3d

in the IPN LOG FILES the return url is not the same and actually shows a ‘wait for e-mail message’

http://dutchmailer.com/?s2member_paypal_return=1&s2member_paypal_return_tra=fnIyOmpreklnT29MZE13ZDAxcTBFWHM5bWNMYmFTU1NoVFFQOmY2N2MwZDJlNDllYzE3YjcyODFhYzVhZDk0YjMwMzdhfMRwt1bGl6fBtCEpCrGoshH4reHXMCIGKv2veIZ6nYrRY_aC3K0BannNgiI8x9-RaoWft–d3UN7nRnsTe_FpeVrbGvHH-ovPPQN5pvJFT2aFj6N2Y-qYwiaF7DiRIh2yiUUpBI4ntm8ipOccmNDoGXHz-dzT3jU-7xqZXR3pTNSAe4nLQhyMy4r_uRLaIWlAMDBeODbbg6YJW–M8LvlMTLVX3Air5f3a2IXQqqGxsya6GkbtmHo7KLNMmORXPJEUrXw67pCXldbTwaPh__XJQFsjt7XweCkBIpfOEuuWxatkcDE9DhigNDmPJKFNzYm_2iMtfhx_GiB1hzNHH5No2KCiRFJpT1fqObHOrWeC5mHzsqV12wHNNFCoP8kd38OA

Anyone have a clue, a tip, some direction ? I’m out of idea’s …..