diff --git a/cdcprolific.cpp b/cdcprolific.cpp
index 968fdc65..eceb1df9 100644
--- a/cdcprolific.cpp
+++ b/cdcprolific.cpp
@@ -30,6 +30,9 @@ uint8_t PL2303::Init(uint8_t parent, uint8_t port, bool lowspeed) {
         UsbDevice *p = NULL;
         EpInfo *oldep_ptr = NULL;
         uint8_t num_of_conf; // number of configurations
+#ifdef PL2303_COMPAT
+        enum pl2303_type pltype = unknown;
+#endif
 
         AddressPool &addrPool = pUsb->GetAddressPool();
 
@@ -69,6 +72,18 @@ uint8_t PL2303::Init(uint8_t parent, uint8_t port, bool lowspeed) {
         if(udd->idVendor != PL_VID && CHECK_PID(udd->idProduct))
                 return USB_DEV_CONFIG_ERROR_DEVICE_NOT_SUPPORTED;
 
+        /* determine chip variant */
+#ifdef PL2303_COMPAT
+        if(udd->bDeviceClass == 0x02 )
+                pltype = type_0;
+        else if(udd->bMaxPacketSize0 == 0x40 )
+                pltype = rev_HX;
+        else if(udd->bDeviceClass == 0x00)
+                pltype = type_1;
+        else if(udd->bDeviceClass == 0xff)
+                pltype = type_1;
+#endif
+
         // Save type of PL chip
         wPLType = udd->bcdDevice;
 
@@ -145,6 +160,28 @@ uint8_t PL2303::Init(uint8_t parent, uint8_t port, bool lowspeed) {
         if(rcode)
                 goto FailSetConfDescr;
 
+#ifdef PL2303_COMPAT
+        /* Shamanic dance - sending Prolific init data as-is */
+        vendorRead( 0x84, 0x84, 0, buf );
+        vendorWrite( 0x04, 0x04, 0 );
+        vendorRead( 0x84, 0x84, 0, buf );
+        vendorRead( 0x83, 0x83, 0, buf );
+        vendorRead( 0x84, 0x84, 0, buf );
+        vendorWrite( 0x04, 0x04, 1 );
+        vendorRead( 0x84, 0x84, 0, buf);
+        vendorRead( 0x83, 0x83, 0, buf);
+        vendorWrite( 0, 0, 1 );
+        vendorWrite( 1, 0, 0 );
+        if( pltype == rev_HX ) {
+                vendorWrite( 2, 0, 0x44 );
+                vendorWrite( 0x06, 0x06, 0 ); // From W7 init
+        }
+        else {
+                vendorWrite( 2, 0, 0x24 );
+        }
+        /* Shamanic dance end */
+#endif
+        /* Calling post-init callback */
         rcode = pAsync->OnInit(this);
 
         if(rcode)
diff --git a/cdcprolific.h b/cdcprolific.h
index 15839550..49914664 100644
--- a/cdcprolific.h
+++ b/cdcprolific.h
@@ -19,6 +19,8 @@ e-mail   :  support@circuitsathome.com
 
 #include "cdcacm.h"
 
+//#define PL2303_COMPAT // Uncomment it if you have compatibility problems
+
 #define PL_VID                                  0x067B
 #define CHECK_PID(pid)                          ( pid != 0x2303 && pid != 0x0609 )
 
@@ -109,8 +111,9 @@ enum tXO_State {
 
 enum pl2303_type {
         unknown,
-        type_1, /* don't know the difference between type 0 and */
-        rev_X, /* type 1, until someone from prolific tells us... */
+        type_0, /* don't know the difference between type 0 and */
+        type_1, /* type 1, until someone from prolific tells us... */
+        rev_X,
         rev_HX, /* HX version of the pl2303 chip */
         rev_H
 };
@@ -130,6 +133,27 @@ public:
 
         //// UsbConfigXtracter implementation
         //virtual void EndpointXtract(uint8_t conf, uint8_t iface, uint8_t alt, uint8_t proto, const USB_ENDPOINT_DESCRIPTOR *ep);
+
+#ifdef PL2303_COMPAT
+private:
+        /* Prolific proprietary requests */
+        uint8_t vendorRead( uint8_t val_lo, uint8_t val_hi, uint16_t index, uint8_t* buf );
+        uint8_t vendorWrite( uint8_t val_lo, uint8_t val_hi, uint8_t index );
+#endif
 };
 
+#ifdef PL2303_COMPAT
+/* vendor read request */
+inline uint8_t PL2303::vendorRead( uint8_t val_lo, uint8_t val_hi, uint16_t index, uint8_t* buf )
+{
+        return( pUsb->ctrlReq(bAddress, 0, VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, val_lo, val_hi, index, 1, 1, buf, NULL ));
+}
+
+/* vendor write request */
+inline uint8_t PL2303::vendorWrite( uint8_t val_lo, uint8_t val_hi, uint8_t index )
+{
+        return( pUsb->ctrlReq(bAddress, 0, VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, val_lo, val_hi, index, 0, 0, NULL, NULL ));
+}
+#endif
+
 #endif // __CDCPROLIFIC_H__