Hand #1048
You are South, North deals, EW Vul, IMPs
A 
K10986 
87 
AJ764
| West | North | East | South |
|---|---|---|---|
| Pass | 1 |
1 |
|
| 1 |
3* |
3 |
4 |
| 5 |
Pass | Pass | Pass |
*Preemptive
Do you know what's going on? Why has LHO preferred to play 5 despite hearing about four-card spade support opposite?
WHAT'S YOUR LEAD?