Transaction gas sent as number instead of hexa string

[thaarok]

When running against sepolia.infura.io, I get following error:

failed:  eth_sendUserOperation error: {"message":"Cannot read properties of undefined (reading 'slice')"} TypeError: Cannot read properties of undefined (reading 'slice')
    at decodeRevertReason (/home/jkalina/Fantom/bundler/packages/utils/dist/src/decodeRevertReason.js:23:28)
    at ValidationManager._simulateHandleOps (/home/jkalina/Fantom/bundler/packages/validation-manager/dist/src/ValidationManager.js:159:65)
    at processTicksAndRejections (node:internal/process/task_queues:105:5)
    at async ValidationManager.validateUserOp (/home/jkalina/Fantom/bundler/packages/validation-manager/dist/src/ValidationManager.js:314:13)

When I add more logging to get the original error (which it is unable to decode):

Error: processing response error (body="{\"jsonrpc\":\"2.0\",\"id\":64,\"error\":{\"code\":-32602,\"message\":\"invalid argument 0: json: cannot unmarshal non-string into Go struct field TransactionArgs.gas of type hexutil.Uint64\"}}\n", error={"code":-32602}, 
requestBody="{\"method\":\"eth_call\",\"params\":[{\"to\":\"0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108\",\"data\":\"0x...\",\"authorizationList\":null,\"gas\":143155},\"latest\"],\"id\":64,\"jsonrpc\":\"2.0\"}", requestMethod="POST", url="https://sepolia.infura.io/v3/...", code=SERVER_ERROR, version=web/5.7.1)

The issue seems to be in:

bundler/packages/validation-manager/src/ValidationManager.ts

Line 218 in c70c909

gas: sum(prevg, userOp.verificationGasLimit, userOp.paymasterVerificationGasLimit).toNumber()

As specified in geth doc, the gas should be sent as a hexa string:
https://geth.ethereum.org/docs/interacting-with-geth/rpc/objects

When I add the conversion like this:

gas: '0x'+sum(prevg, userOp.verificationGasLimit, userOp.paymasterVerificationGasLimit).toNumber().toString(16)

It solves the issue for me.
Can this be fixed in the upstream? Thanks!

Note:
I have also tried to just use .toHexString() instead of .toNumber(), but it produces a leading zero digit, which is also not accepted by geth/Infura:

\"gas\":\"0x022f33\"
invalid argument 0: json: cannot unmarshal hex number with leading zero digits into Go struct field TransactionArgs.gas of type hexutil.Uint64