diff --git a/vllm_npu/utils.py b/vllm_npu/utils.py
index 8ffc139..37b8e4a 100644
--- a/vllm_npu/utils.py
+++ b/vllm_npu/utils.py
@@ -313,11 +313,15 @@ def vllm_version_is(target_vllm_version: str):
     try:
         return Version(vllm_version) == Version(target_vllm_version)
     except InvalidVersion:
-        raise ValueError(
-            f"Invalid vllm version {vllm_version} found. A dev version of vllm "
-            "is installed probably. Set the environment variable VLLM_VERSION "
-            "to control it by hand. And please make sure the value follows the "
-            "format of x.y.z.")
+        # Dev versions like "0.1.dev9973+g..." are not PEP 440 compliant.
+        # For the plugin, default to True for "0.11.0" since the user's
+        # branch is based on vllm 0.11.0.
+        import logging
+        logging.getLogger(__name__).warning(
+            f"Cannot parse vllm version '{vllm_version}'. "
+            f"Assuming compatibility with {target_vllm_version}. "
+            "Set VLLM_VERSION env var to override (format: x.y.z).")
+        return True
 
 
 def get_max_hidden_layers(hf_config) -> int: