How To Exec Stored Proc Dynamically

Hello
I have 2 procedures setup in master database, sp_RebuildIndexesMain and
sp_RebuildIndexesSub

The Sub just shows and execute DBCC commands for passed database
context

sp_RebuildIndexesSub(@listOnly bit=0, @maxfrag Decimal=30.0)

This runs fine if I do pubs..sp_RebuildIndexesSub
However when run thru. the Main proc, I get Incorrect syntax near
'pubs'.
The main proc is

Create Proc sp_RebuildIndexesMain(@dbName sysname, @listOnly bit=0,
@maxFrag Decimal=30.0)
As
Begin
Set NOCOUNT ON

Declare crDbs CURSOR For
Select CATALOG_NAME From INFORMATION_SCHEMA.SCHEMATA
Where CATALOG_NAME NOT IN ('tempdb', 'master', 'msdb', 'model',
'distribution', 'Northwind', 'pubs')
And CATALOG_NAME Like @dbName

Declare @execstr nvarchar(2000)

Open crDbs
Fetch crDbs INTO @dbName
If (@@FETCH_STATUS<>0) --Then no matching databases
Begin
Close crDbs
Deallocate CrDbs
Print 'No databases were found that match ''' + @dbName + ''''
Return -1
End

While(@@FETCH_STATUS=0)
Begin
Print Char(13) + 'Rebuilding indexes on ' + @dbName
Print Char(13)
Set @execstr = @dbName + '..sp_RebuildIndexesSub '
EXEC sp_executesql @execstr, N'@listOnly bit, @maxFrag Decimal',
@listOnly, @maxFrag
Fetch crDbs INTO @dbName
End
Close crDbs
Deallocate CrDbs
Return 0
End

thanks
Sunit
Join Bytes!