diff --git a/Resource/Init/gs_init.ps b/Resource/Init/gs_init.ps
index 55a785e..be77534 100644
--- a/Resource/Init/gs_init.ps
+++ b/Resource/Init/gs_init.ps
@@ -2607,4 +2607,6 @@ WRITESYSTEMDICT {
 % be 'true' in some cases.
 userdict /AGM_preserve_spots //false put
 
+.opvpactivatepathcontrol
+
 % The interpreter will run the initial procedure (start).
diff --git a/base/gslibctx.c b/base/gslibctx.c
index 1ed6093..14fb57c 100644
--- a/base/gslibctx.c
+++ b/base/gslibctx.c
@@ -435,3 +435,27 @@ gs_check_file_permission (gs_memory_t *mem, const char *fname, const int len, co
     }
     return code;
 }
+
+void
+opvp_activate_path_control(gs_memory_t *mem, int enable)
+{
+    gs_lib_ctx_core_t *core;
+
+    if (mem == NULL || mem->gs_lib_ctx == NULL ||
+        (core = mem->gs_lib_ctx->core) == NULL)
+        return;
+
+    core->opvp_path_control_active = enable;
+}
+
+int
+opvp_is_path_control_active(const gs_memory_t *mem)
+{
+    gs_lib_ctx_core_t *core;
+
+    if (mem == NULL || mem->gs_lib_ctx == NULL ||
+        (core = mem->gs_lib_ctx->core) == NULL)
+        return 0;
+
+    return core->opvp_path_control_active;
+}
diff --git a/base/gslibctx.h b/base/gslibctx.h
index 1481cb5..e4b3924 100644
--- a/base/gslibctx.h
+++ b/base/gslibctx.h
@@ -61,6 +61,8 @@ typedef struct {
     bool CPSI_mode;
     int scanconverter;
     int act_on_uel;
+
+    int opvp_path_control_active;
 } gs_lib_ctx_core_t;
 
 typedef struct gs_lib_ctx_s
@@ -167,4 +169,10 @@ int sjpxd_create(gs_memory_t *mem);
 
 void sjpxd_destroy(gs_memory_t *mem);
 
+void
+opvp_activate_path_control(gs_memory_t *mem, int enable);
+
+int
+opvp_is_path_control_active(const gs_memory_t *mem);
+
 #endif /* GSLIBCTX_H */
diff --git a/contrib/opvp/gdevopvp.c b/contrib/opvp/gdevopvp.c
index 9a6b45b..9693673 100644
--- a/contrib/opvp/gdevopvp.c
+++ b/contrib/opvp/gdevopvp.c
@@ -185,7 +185,7 @@ static  int opvp_copy_color(gx_device *, const byte *, int, int,
 static  int _get_params(gs_param_list *);
 static  int opvp_get_params(gx_device *, gs_param_list *);
 static  int oprp_get_params(gx_device *, gs_param_list *);
-static  int _put_params(gs_param_list *);
+static  int _put_params(gx_device *, gs_param_list *);
 static  int opvp_put_params(gx_device *, gs_param_list *);
 static  int oprp_put_params(gx_device *, gs_param_list *);
 static  int opvp_fill_path(gx_device *, const gs_gstate *, gx_path *,
@@ -3039,7 +3039,7 @@ _get_params(gs_param_list *plist)
     /* vector driver name */
     pname = "Driver";
     vdps.data = (byte *)vectorDriver;
-    vdps.size = (vectorDriver ? strlen(vectorDriver) + 1 : 0);
+    vdps.size = (vectorDriver ? strlen(vectorDriver) : 0);
     vdps.persistent = false;
     code = param_write_string(plist, pname, &vdps);
     if (code) ecode = code;
@@ -3176,7 +3176,7 @@ oprp_get_params(gx_device *dev, gs_param_list *plist)
  * put params
  */
 static  int
-_put_params(gs_param_list *plist)
+_put_params(gx_device *dev, gs_param_list *plist)
 {
     int code;
     int ecode = 0;
@@ -3198,6 +3198,12 @@ _put_params(gs_param_list *plist)
     code = param_read_string(plist, pname, &vdps);
     switch (code) {
     case 0:
+        if (opvp_is_path_control_active(dev->memory)
+            && (!vectorDriver || strlen(vectorDriver) != vdps.size
+                || memcmp(vectorDriver, vdps.data, vdps.size) != 0)) {
+            param_signal_error(plist, pname, gs_error_invalidaccess);
+            return_error(gs_error_invalidaccess);
+        }
         buff = realloc(buff, vdps.size + 1);
         memcpy(buff, vdps.data, vdps.size);
         buff[vdps.size] = 0;
@@ -3399,7 +3405,7 @@ opvp_put_params(gx_device *dev, gs_param_list *plist)
     int code;
 
     /* put params */
-    code = _put_params(plist);
+    code = _put_params(dev, plist);
     if (code) return code;
 
     /* put default params */
@@ -3415,7 +3421,7 @@ oprp_put_params(gx_device *dev, gs_param_list *plist)
     int code;
 
     /* put params */
-    code = _put_params(plist);
+    code = _put_params(dev, plist);
     if (code) return code;
 
     /* put default params */
diff --git a/psi/zfile.c b/psi/zfile.c
index 271a1a0..05b8203 100644
--- a/psi/zfile.c
+++ b/psi/zfile.c
@@ -875,6 +875,12 @@ static int zgetfilename(i_ctx_t *i_ctx_p)
     return 0;
 }
 
+static int zopvpactivatepathcontrol(i_ctx_t *i_ctx_p)
+{
+    opvp_activate_path_control(imemory, 1);
+    return 0;
+}
+
 /* ------ Initialization procedure ------ */
 
 const op_def zfile_op_defs[] =
@@ -893,6 +899,7 @@ const op_def zfile_op_defs[] =
     {"0%file_continue", file_continue},
     {"0%execfile_finish", execfile_finish},
     {"1.getfilename", zgetfilename},
+    {"0.opvpactivatepathcontrol", zopvpactivatepathcontrol},
     op_def_end(0)
 };