Okay... I might actually have some time this weekend to mess with this.

Mart would you mind running the following code on the box where you had multiple adapters, and post the results?

Code:
 
Break On
$strComputer = "."
$objWMIService = GetObject("winmgmts:\\" + $strComputer + "\root\cimv2")
$colItems = $objWMIService.ExecQuery("Select * from Win32_NetworkAdapterConfiguration",,48)
For each $objItem in $colItems
  "ArpAlwaysSourceRoute: " + $objItem.ArpAlwaysSourceRoute ?
  "ArpUseEtherSNAP: " + $objItem.ArpUseEtherSNAP ?
  "Caption: " + $objItem.Caption ?
  "DatabasePath: " + $objItem.DatabasePath ?
  "DeadGWDetectEnabled: " + $objItem.DeadGWDetectEnabled ?
  For each $Item in $objItem.DefaultIPGateway
    "*DefaultIPGateway: " + $Item ?
  Next
  "DefaultTOS: " + $objItem.DefaultTOS ?
  "DefaultTTL: " + $objItem.DefaultTTL ?
  "Description: " + $objItem.Description ?
  "DHCPEnabled: " + $objItem.DHCPEnabled ?
  "DHCPLeaseExpires: " + $objItem.DHCPLeaseExpires ?
  "DHCPLeaseObtained: " + $objItem.DHCPLeaseObtained ?
  "DHCPServer: " + $objItem.DHCPServer ?
  "DNSDomain: " + $objItem.DNSDomain ?
  For each $Item in $objItem.DNSDomainSuffixSearchOrder
    "*DNSDomainSuffixSearchOrder: " + $Item ?
  Next
  "DNSEnabledForWINSResolution: " + $objItem.DNSEnabledForWINSResolution ?
  "DNSHostName: " + $objItem.DNSHostName ?
  For each $Item in $objItem.DNSServerSearchOrder
    "*DNSServerSearchOrder: " + $Item ?
  Next
  "DomainDNSRegistrationEnabled: " + $objItem.DomainDNSRegistrationEnabled ?
  "ForwardBufferMemory: " + $objItem.ForwardBufferMemory ?
  "FullDNSRegistrationEnabled: " + $objItem.FullDNSRegistrationEnabled ?
  For each $Item in $objItem.GatewayCostMetric
    "*GatewayCostMetric: " + $Item ?
  Next
  "IGMPLevel: " + $objItem.IGMPLevel ?
  "Index: " + $objItem.Index ?
  For each $Item in $objItem.IPAddress
    "*IPAddress: " + $Item ?
  Next
  "IPConnectionMetric: " + $objItem.IPConnectionMetric ?
  "IPEnabled: " + $objItem.IPEnabled ?
  "IPFilterSecurityEnabled: " + $objItem.IPFilterSecurityEnabled ?
  "IPPortSecurityEnabled: " + $objItem.IPPortSecurityEnabled ?
  For each $Item in $objItem.IPSecPermitIPProtocols
    "*IPSecPermitIPProtocols: " + $Item ?
  Next
  For each $Item in $objItem.IPSecPermitTCPPorts
    "*IPSecPermitTCPPorts: " + $Item ?
  Next
  For each $Item in $objItem.IPSecPermitUDPPorts
    "*IPSecPermitUDPPorts: " + $Item ?
  Next
  For each $Item in $objItem.IPSubnet
    "*IPSubnet: " + $Item ?
  Next
  "IPUseZeroBroadcast: " + $objItem.IPUseZeroBroadcast ?
  "IPXAddress: " + $objItem.IPXAddress ?
  "IPXEnabled: " + $objItem.IPXEnabled ?
  "IPXFrameType: " + $objItem.IPXFrameType ?
  "IPXMediaType: " + $objItem.IPXMediaType ?
  "IPXNetworkNumber: " + $objItem.IPXNetworkNumber ?
  "IPXVirtualNetNumber: " + $objItem.IPXVirtualNetNumber ?
  "KeepAliveInterval: " + $objItem.KeepAliveInterval ?
  "KeepAliveTime: " + $objItem.KeepAliveTime ?
  "MACAddress: " + $objItem.MACAddress ?
  "MTU: " + $objItem.MTU ?
  "NumForwardPackets: " + $objItem.NumForwardPackets ?
  "PMTUBHDetectEnabled: " + $objItem.PMTUBHDetectEnabled ?
  "PMTUDiscoveryEnabled: " + $objItem.PMTUDiscoveryEnabled ?
  "ServiceName: " + $objItem.ServiceName ?
  "SettingID: " + $objItem.SettingID ?
  "TcpipNetbiosOptions: " + $objItem.TcpipNetbiosOptions ?
  "TcpMaxConnectRetransmissions: " + $objItem.TcpMaxConnectRetransmissions ?
  "TcpMaxDataRetransmissions: " + $objItem.TcpMaxDataRetransmissions ?
  "TcpNumConnections: " + $objItem.TcpNumConnections ?
  "TcpUseRFC1122UrgentPointer: " + $objItem.TcpUseRFC1122UrgentPointer ?
  "TcpWindowSize: " + $objItem.TcpWindowSize ?
  "WINSEnableLMHostsLookup: " + $objItem.WINSEnableLMHostsLookup ?
  "WINSHostLookupFile: " + $objItem.WINSHostLookupFile ?
  "WINSPrimaryServer: " + $objItem.WINSPrimaryServer ?
  "WINSScopeID: " + $objItem.WINSScopeID ?
  "WINSSecondaryServer: " + $objItem.WINSSecondaryServer ?
  ?
Next